Thermoelectric generator, thermoelectric generation method, electrical signal detecting device, and electrical signal detecting method

ABSTRACT

A thermoelectric generation method using a thermoelectric generator includes: placing a thermoelectric generator in a temperature-changing atmosphere; drawing to outside a current that is generated due to a temperature difference between first and second support members when the temperature of the second support member is higher than that of the first support member, and that flows from a second thermoelectric conversion member to a first thermoelectric conversion member, using first and second output sections as a positive terminal and a negative terminal, respectively; and drawing to outside a current that is generated due to a temperature difference between the first and second support members when the temperature of the first support member is higher than that of the second support member, and that flows from a fourth thermoelectric conversion member to a third thermoelectric conversion member, using third and fourth output sections as a positive terminal and a negative terminal, respectively.

CROSS REFERENCES TO RELATED APPLICATIONS

This application is a divisional of U.S. patent application Ser. No.12/958,977, filed on Dec. 2, 2010, issued as U.S. Pat. No. 8,674,208 onMar. 18, 2014, which claims priority to Japanese Patent Application JP2009-279290 filed on Dec. 9, 2009; JP 2010-194001 filed on Aug. 31,2010; and JP 2010-241722 filed on Oct. 28, 2010, the entire contents ofwhich are hereby incorporated by reference.

BACKGROUND

The present disclosure relates to thermoelectric generators,thermoelectric generation methods, electrical signal detecting devices,and electrical signal detecting methods.

Thermoelectric generators that utilize temperature differences include aheat receiver, a heat radiator, and a thermoelectric conversion elementdisposed between the heat receiver and the heat radiator. For example,portable communications devices (see JP-A-2004-056866) and wrist watches(see JP-A-2000-147161) are known examples of devices using suchthermoelectric generators.

SUMMARY

The thermoelectric generator requires temperature differences betweenthe heat receiver and the heat radiator. Thus, for example,thermoelectric generation fails in the absence of temperaturedifferences between the heat receiver and the heat radiator as a resultof heat transfer from the heat receiver to the heat radiator through thethermoelectric conversion element. Absent the influx of heat from theheat source into the heat receiver, no electricity is generated in thefirst place. Thermoelectric generation is therefore difficult when thethermoelectric generator of related art is placed in, for example, anordinary living environment, specifically, in a room. Further, thethermoelectric generator of related art can constantly effectthermoelectric generation only under limited settings. Constantthermoelectric generation over an ordinary temperature range isparticularly difficult.

Sensing devices generally require energy, which is typically suppliedfrom batteries or commercial power sources. Replacement or charging ofthe batteries is therefore necessary, and, when wired, use of the deviceis limited. Devices including a power-generating unit that generateselectricity from body temperature are available. However, because thesensing device additionally includes the power-generating unit, thedevice is increased in size or in complexity.

Accordingly, there is a need for a thermoelectric generator, athermoelectric generation method, an electrical signal detecting device,and an electrical signal detecting method that enable thermoelectricgeneration without a heat source.

According to First or Second Embodiment, there is provided athermoelectric generator that includes:

(A) a first support member;

(B) a second support member disposed opposite the first support member;

(C) a thermoelectric conversion element disposed between the firstsupport member and the second support member; and

(D) a first output section and a second output section both of which areconnected to the thermoelectric conversion element,

wherein the thermoelectric conversion element includes:

(C-1) a first thermoelectric conversion member disposed between thefirst support member and the second support member; and

(C-2) a second thermoelectric conversion member disposed between thefirst support member and the second support member, and that is made ofa material different from that of the first thermoelectric conversionmember, and is electrically connected in series to the firstthermoelectric conversion member,

the first output section is connected to an end portion of firstthermoelectric conversion member on the first support member side, and

the second output section is connected to an end portion of the secondthermoelectric conversion member on the first support member side.

In the thermoelectric generator according to First Embodiment, therelations τ_(SM1)>τ_(SM2), and S₁₂≠S₂₂ are established, where S₁₂ is thearea of a second surface of the first thermoelectric conversion memberin contact with the second support member, provided that S₁₁>S₁₂, whereS₁₁ is the area of a first surface of the first thermoelectricconversion member in contact with the first support member, S₂₂ is thearea of a second surface of the second thermoelectric conversion memberin contact with the second support member, provided that S₂₁>S₂₂, whereS₂₁ is the area of a first surface of the second thermoelectricconversion member in contact with the first support member, τ_(SM1) isthe thermal response time constant of the first support member, andτ_(SM2) is the thermal response time constant of the second supportmember.

In the thermoelectric generator according to Second Embodiment, therelations τ_(SM1)>τ_(SM2), and VL₁≠VL₂ are established, where VL₁ is thevolume of the first thermoelectric conversion member, VL₂ is the volumeof the second thermoelectric conversion member, τ_(SM1) is the thermalresponse time constant of the first support member, and τ_(SM2) is thethermal response time constant of the second support member.

According to Third Embodiment, there is provided a thermoelectricgenerator that includes:

(A) a first support member;

(B) a second support member disposed opposite the first support member;

(C) a first thermoelectric conversion element disposed between the firstsupport member and the second support member;

(D) a second thermoelectric conversion element disposed between thefirst support member and the second support member; and

(E) a first output section and a second output section,

wherein the first thermoelectric conversion element includes a firstthermoelectric conversion member A in contact with the second supportmember, and a first thermoelectric conversion member B in contact withthe first support member, the first thermoelectric conversion member Aand the first thermoelectric conversion member B being disposed incontact with each other, and

the second thermoelectric conversion element includes a secondthermoelectric conversion member A in contact with the first supportmember, and a second thermoelectric conversion member B in contact withthe second support member, the second thermoelectric conversion member Aand the second thermoelectric conversion member B being disposed incontact with each other,

wherein the first thermoelectric conversion element and the secondthermoelectric conversion element are electrically connected to eachother in series,

the first output section is connected to an end portion of the firstthermoelectric conversion member B,

the second output section is connected to an end portion of the secondthermoelectric conversion member A, and

the relation τ_(SM1)≠τ_(SM2) is established, where τ_(SM1) is thethermal response time constant of the first support member, and τ_(SM2)is the thermal response time constant of the second support member.

According to Fourth Embodiment, there is provided a thermoelectricgenerator that includes:

(A) a first support member;

(B) a second support member disposed opposite the first support member;

(C) a first thermoelectric conversion element disposed between the firstsupport member and the second support member;

(D) a second thermoelectric conversion element disposed between thefirst support member and the second support member; and

(E) a first output section, a second output section, a third outputsection, and a fourth output section,

wherein the first thermoelectric conversion element includes:

(C-1) a first thermoelectric conversion member disposed between thefirst support member and the second support member; and

(C-2) a second thermoelectric conversion member disposed between thefirst support member and the second support member, and that is made ofa material different from that of the first thermoelectric conversionmember, and is electrically connected in series to the firstthermoelectric conversion member,

the second thermoelectric conversion element includes:

(D-1) a third thermoelectric conversion member disposed between thefirst support member and the second support member; and

(D-2) a fourth thermoelectric conversion member disposed between thefirst support member and the second support member, and that is made ofa material different from that of the third thermoelectric conversionmember, and is electrically connected in series to the thirdthermoelectric conversion member,

the first output section is connected to the first thermoelectricconversion member,

the second output section is connected to the second thermoelectricconversion member,

the third output section is connected to the third thermoelectricconversion member,

wherein the fourth output section is connected to the fourththermoelectric conversion member, and

the relation τ_(SM1)≠τ_(SM2) is established, where τ_(SM1) is thethermal response time constant of the first support member, and τ_(SM2)is the thermal response time constant of the second support member.

According to Fifth Embodiment, there is provided a thermoelectricgenerator that includes:

(A) a first support member;

(B) a second support member disposed opposite the first support member;

(C) a first thermoelectric conversion element disposed between the firstsupport member and the second support member;

(D) a second thermoelectric conversion element disposed between thefirst support member and the second support member;

(E) a third thermoelectric conversion element disposed between the firstsupport member and the second support member;

(F) a fourth thermoelectric conversion element disposed between thefirst support member and the second support member; and

(G) a first output section, a second output section, a third outputsection, and a fourth output section,

wherein the first thermoelectric conversion element includes a firstthermoelectric conversion member A in contact with the second supportmember, and a first thermoelectric conversion member B in contact withthe first support member, the first thermoelectric conversion member Aand the first thermoelectric conversion member B being disposed incontact with each other,

the second thermoelectric conversion element includes a secondthermoelectric conversion member A in contact with the first supportmember, and a second thermoelectric conversion member B in contact withthe second support member, the second thermoelectric conversion member Aand the second thermoelectric conversion member B being disposed incontact with each other,

the third thermoelectric conversion element includes a thirdthermoelectric conversion member A in contact with the second supportmember, and a third thermoelectric conversion member B in contact withthe first support member, the third thermoelectric conversion member Aand the third thermoelectric conversion member B being disposed incontact with each other,

the fourth thermoelectric conversion element includes a fourththermoelectric conversion member A in contact with the first supportmember, and a fourth thermoelectric conversion member B in contact withthe second support member, the fourth thermoelectric conversion member Aand the fourth thermoelectric conversion member B being disposed incontact with each other,

the first thermoelectric conversion element and the secondthermoelectric conversion element are electrically connected to eachother in series,

the third thermoelectric conversion element and the fourththermoelectric conversion element are electrically connected to eachother in series,

the first output section is connected to the first thermoelectricconversion element,

the second output section is connected to the second thermoelectricconversion element,

the third output section is connected to the third thermoelectricconversion element,

the fourth output section is connected to the fourth thermoelectricconversion element, and

the relation τ_(SM1)≠τ_(SM2) is established, where τ_(SM1) is thethermal response time constant of the first support member, and τ_(SM2)is the thermal response time constant of the second support member.

According to First Embodiment, there is provided a thermoelectricgeneration method that uses the thermoelectric generator of FirstEmbodiment. According to Second Embodiment, there is provided athermoelectric generation method that uses the thermoelectric generatorof Second Embodiment. According to Third Embodiment, there is provided athermoelectric generation method that uses the thermoelectric generatorof Third Embodiment.

The thermoelectric generation methods according to First to ThirdEmbodiments include:

placing the thermoelectric generator in a temperature-changingatmosphere;

drawing to outside a current that is generated due to a temperaturedifference between the first support member and the second supportmember when the temperature of the second support member is higher thanthe temperature of the first support member, and that flows from thesecond thermoelectric conversion member to the first thermoelectricconversion member, using the first output section as a positiveterminal, and the second output section as a negative terminal (thethermoelectric generation methods according to First and SecondEmbodiments), or that flows from the second thermoelectric conversionelement to the first thermoelectric conversion element, using the firstoutput section as a positive terminal, and the second output section asa negative terminal (the thermoelectric generation method according toThird Embodiment).

According to Fourth Embodiment A, there is provided a thermoelectricgeneration method that uses the thermoelectric generator according toFourth Embodiment, and includes the steps of:

placing the thermoelectric generator in a temperature-changingatmosphere;

drawing to outside a current that is generated due to a temperaturedifference between the first support member and the second supportmember when the temperature of the second support member is higher thanthe temperature of the first support member, and that flows from thesecond thermoelectric conversion member to the first thermoelectricconversion member, using the first output section as a positiveterminal, and the second output section as a negative terminal; and

drawing to outside a current that is generated due to a temperaturedifference between the first support member and the second supportmember when the temperature of the first support member is higher thanthe temperature of the second support member, and that flows from thefourth thermoelectric conversion member to the third thermoelectricconversion member, using the third output section as a positiveterminal, and the fourth output section as a negative terminal.

According to Fourth Embodiment B, there is provided a thermoelectricgeneration method in which, according to the thermoelectric generationmethod of Fourth Embodiment A, a current that is generated due to atemperature difference between the first support member and the secondsupport member when the temperature of the second support member ishigher than the temperature of the first support member, and that flowsfrom the second thermoelectric conversion member to the firstthermoelectric conversion member is drawn to outside using the firstoutput section as a positive terminal, and the second output section asa negative terminal, and the current that flows from the fourththermoelectric conversion member to the third thermoelectric conversionmember is drawn to outside using the third output section as a positiveterminal, and the fourth output section as a negative terminal, insteadof drawing to outside the current that is generated due to thetemperature difference between the first support member and the secondsupport member when the temperature of the second support member ishigher than the temperature of the first support member, and that flowsfrom the second thermoelectric conversion member to the firstthermoelectric conversion member, using the first output section as apositive terminal, and the second output section as a negative terminal,and instead of drawing to outside the current that is generated due tothe temperature difference between the first support member and thesecond support member when the temperature of the first support memberis higher than the temperature of the second support member, and thatflows from the fourth thermoelectric conversion member to the thirdthermoelectric conversion member, using the third output section as apositive terminal, and the fourth output section as a negative terminal.

According to Fifth Embodiment A, there is provided a thermoelectricgeneration method that uses the thermoelectric generator of FifthEmbodiment, and includes:

placing the thermoelectric generator in a temperature-changingatmosphere;

drawing to outside a current that is generated due to a temperaturedifference between the first support member and the second supportmember when the temperature of the second support member is higher thanthe temperature of the first support member, and that flows from thesecond thermoelectric conversion element to the first thermoelectricconversion element, using the first output section as a positiveterminal, and the second output section as a negative terminal; and

drawing to outside a current that is generated due to a temperaturedifference between the first support member and the second supportmember when the temperature of the first support member is higher thanthe temperature of the second support member, and that flows from thethird thermoelectric conversion element to the fourth thermoelectricconversion element, using the fourth output section as a positiveterminal, and the third output section as a negative terminal.

According to Fifth Embodiment B, there is provided a thermoelectricgeneration method in which, according to the thermoelectric generationmethod of Fifth Embodiment A, a current that is generated due to atemperature difference between the first support member and the secondsupport member when the temperature of the second support member ishigher than the temperature of the first support member, and that flowsfrom the second thermoelectric conversion element to the firstthermoelectric conversion element is drawn to outside using the firstoutput section as a positive terminal, and the second output section asa negative terminal, and the current that flows from the fourththermoelectric conversion element to the third thermoelectric conversionelement is drawn to outside using the third output section as a positiveterminal, and the fourth output section as a negative terminal, insteadof drawing to outside the current that is generated due to thetemperature difference between the first support member and the secondsupport member when the temperature of the second support member ishigher than the temperature of the first support member, and that flowsfrom the second thermoelectric conversion element to the firstthermoelectric conversion element, using the first output section as apositive terminal, and the second output section as a negative terminal,and instead of drawing to outside the current that is generated due tothe temperature difference between the first support member and thesecond support member when the temperature of the first support memberis higher than the temperature of the second support member, and thatflows from the third thermoelectric conversion element to the fourththermoelectric conversion element, using the fourth output section as apositive terminal, and the third output section as a negative terminal.

According to First Embodiment, there is provided an electrical signaldetecting method that uses the thermoelectric generator of FirstEmbodiment. According to Second Embodiment, there is provided anelectrical signal detecting method that uses the thermoelectricgenerator of Second Embodiment. According to Third Embodiment, there isprovided an electrical signal detecting method that uses thethermoelectric generator of Third Embodiment.

The electrical signal detecting methods according to First to ThirdEmbodiments include:

placing the thermoelectric generator in a temperature-changingatmosphere;

drawing to outside a current that is generated due to a temperaturedifference between the first support member and the second supportmember when the temperature of the second support member is higher thanthe temperature of the first support member, and that flows from thesecond thermoelectric conversion member to the first thermoelectricconversion member, using the first output section as a positiveterminal, and the second output section as a negative terminal, thecurrent being drawn as an electrical signal (the electrical signaldetecting methods according to First and Second Embodiments), or thatflows from the second thermoelectric conversion element to the firstthermoelectric conversion element, using the first output section as apositive terminal, and the second output section as a negative terminal,the current being drawn as an electrical signal (the electrical signaldetecting method according to Third Embodiment); and

obtaining different kinds of electrical signals from the electricalsignal.

According to Fourth Embodiment A, there is provided an electrical signaldetecting method that uses the thermoelectric generator of FourthEmbodiment, and includes:

placing the thermoelectric generator in a temperature-changingatmosphere;

drawing to outside a current that is generated due to a temperaturedifference between the first support member and the second supportmember when the temperature of the second support member is higher thanthe temperature of the first support member, and that flows from thesecond thermoelectric conversion member to the first thermoelectricconversion member, using the first output section as a positiveterminal, and the second output section as a negative terminal, thecurrent being drawn as an electrical signal; and

drawing to outside a current that is generated due to a temperaturedifference between the first support member and the second supportmember when the temperature of the first support member is higher thanthe temperature of the second support member, and that flows from thefourth thermoelectric conversion member to the third thermoelectricconversion member, using the third output section as a positiveterminal, and the fourth output section as a negative terminal, thecurrent being drawn as an electrical signal; and

obtaining different kinds of electrical signals from the electricalsignals.

According to Fourth Embodiment B, there is provided an electrical signaldetecting method in which, according to the electrical signal detectingmethod of Fourth Embodiment A, a current that is generated due to atemperature difference between the first support member and the secondsupport member when the temperature of the second support member ishigher than the temperature of the first support member, and that flowsfrom the second thermoelectric conversion member to the firstthermoelectric conversion member is drawn to outside as an electricalsignal using the first output section as a positive terminal, and thesecond output section as a negative terminal, and the current that flowsfrom the fourth thermoelectric conversion member to the thirdthermoelectric conversion member is drawn as an electrical signal usingthe third output section as a positive terminal, and the fourth outputsection as a negative terminal, instead of drawing to outside thecurrent that is generated due to the temperature difference between thefirst support member and the second support member when the temperatureof the second support member is higher than the temperature of the firstsupport member, and that flows from the second thermoelectric conversionmember to the first thermoelectric conversion member, using the firstoutput section as a positive terminal, and the second output section asa negative terminal, and instead of drawing to outside the current thatis generated due to the temperature difference between the first supportmember and the second support member when the temperature of the firstsupport member is higher than the temperature of the second supportmember, and that flows from the fourth thermoelectric conversion memberto the third thermoelectric conversion member, using the third outputsection as a positive terminal, and the fourth output section as anegative terminal, and in which different kinds of electrical signalsare obtained from the electrical signals.

According to Fifth Embodiment A, there is provided an electrical signaldetecting method that uses the thermoelectric generator of FifthEmbodiment, and includes:

placing the thermoelectric generator in a temperature-changingatmosphere;

drawing to outside a current that is generated due to a temperaturedifference between the first support member and the second supportmember when the temperature of the second support member is higher thanthe temperature of the first support member, and that flows from thesecond thermoelectric conversion element to the first thermoelectricconversion element, using the first output section as a positiveterminal, and the second output section as a negative terminal, thecurrent being drawn as an electrical signal; and

drawing to outside a current that is generated due to a temperaturedifference between the first support member and the second supportmember when the temperature of the first support member is higher thanthe temperature of the second support member, and that flows from thethird thermoelectric conversion element to the fourth thermoelectricconversion element, using the fourth output section as a positiveterminal, and the third output section as a negative terminal, thecurrent being drawn as an electrical signal; and

obtaining different kinds of electrical signals from the electricalsignals.

According to Fifth Embodiment B, there is provided an electrical signaldetecting method in which, according to the electrical signal detectingmethod of Fifth Embodiment A, a current that is generated due to atemperature difference between the first support member and the secondsupport member when the temperature of the second support member ishigher than the temperature of the first support member, and the flowfrom the second thermoelectric conversion element to the firstthermoelectric conversion element is drawn to outside as an electricalsignal using the first output section as a positive terminal, and thesecond output section as a negative terminal, and the current that flowsfrom the fourth thermoelectric conversion element to the thirdthermoelectric conversion element is drawn to outside as an electricalsignal using the third output section as a positive terminal, and thefourth output section as a negative terminal, instead of drawing tooutside the current that is generated due to the temperature differencebetween the first support member and the second support member when thetemperature of the second support member is higher than the temperatureof the first support member, and that flows from the secondthermoelectric conversion element to the first thermoelectric conversionelement, using the first output section as a positive terminal, and thesecond output section as a negative terminal, and instead of drawing tooutside the current that is generated due to the temperature differencebetween the first support member and the second support member when thetemperature of the first support member is higher than the temperatureof the second support member, and that flows from the thirdthermoelectric conversion element to the fourth thermoelectricconversion element, using the fourth output section as a positiveterminal, and the third output section as a negative terminal, and inwhich different kinds of electrical signals are obtained from theelectrical signals.

According to an embodiment, there is provided an electrical signaldetecting device that includes at least two of the thermoelectricgenerators of First to Fifth Embodiments, and in which the currentobtained from each thermoelectric generator is obtained as an electricalsignal.

Specifically, the electrical signal detecting device according to theembodiment may be of a form including:

(01) at least one thermoelectric generator according to FirstEmbodiment, and at least one thermoelectric generator according toSecond Embodiment;

(02) at least one thermoelectric generator according to FirstEmbodiment, and at least one thermoelectric generator according to ThirdEmbodiment;

(03) at least one thermoelectric generator according to FirstEmbodiment, and at least one thermoelectric generator according toFourth Embodiment;

(04) at least one thermoelectric generator according to FirstEmbodiment, and at least one thermoelectric generator according to FifthEmbodiment;

(05) at least one thermoelectric generator according to SecondEmbodiment, and at least one thermoelectric generator according to ThirdEmbodiment;

(06) at least one thermoelectric generator according to SecondEmbodiment, and at least one thermoelectric generator according toFourth Embodiment;

(07) at least one thermoelectric generator according to SecondEmbodiment, and at least one thermoelectric generator according to FifthEmbodiment;

(08) at least one thermoelectric generator according to ThirdEmbodiment, and at least one thermoelectric generator according toFourth Embodiment;

(09) at least one thermoelectric generator according to ThirdEmbodiment, and at least one thermoelectric generator according to FifthEmbodiment; or

(10) at least one thermoelectric generator according to FourthEmbodiment, and at least one thermoelectric generator according to FifthEmbodiment.

Aside from these ten combinations, the electrical signal detectingdevice may be any of ten combinations selecting three kinds, forexample, three thermoelectric generators, any of five combinationsselecting four kinds, for example, four thermoelectric generators, orone combination selecting five kinds, for example, five thermoelectricgenerators from the thermoelectric generators according to First throughFifth Embodiments.

The thermal response time constant τ_(SM1) of the first support member,and the thermal response time constant τ_(SM2) of the second supportmember are different in the thermoelectric generators according to Firstto Fifth Embodiments, in the thermoelectric generator used for thethermoelectric generation methods according to First to FifthEmbodiments, in the electrical signal detecting methods according toFirst to Fifth Embodiments, and in the electrical signal detectingdevice of the embodiment. Thus, a temperature difference occurs betweenthe temperature of the first support member and the temperature of thesecond support member upon placing the thermoelectric generator in atemperature-changing atmosphere. As a result, thermoelectric generationoccurs in the thermoelectric conversion element, the firstthermoelectric conversion element, or the second thermoelectricconversion element. Specifically, thermoelectric generation, orgeneration of an electrical signal is possible without a heat source,provided that there are temperature changes or temperature fluctuationsin the environment or atmosphere in which the thermoelectric generatoris placed. This enables, for example, remote monitoring or remotesensing in remote places, and enables a power-generating unit to beinstalled in places where reinstallation is difficult, or in placeswhere placement of wires or interconnections is physically difficult.Further, designing and layout of the power-generating unit can be mademore freely.

In the electrical signal detecting methods according to First to FifthEmbodiments, different kinds of electrical signals are obtained from onekind of electrical signal. Further, in the electrical signal detectingdevice of the embodiment, different kinds of electrical signals areobtained from a single electrical signal detecting device. Further, theelectrical signal detecting device itself serves as a power-generatingunit. The electrical signal detecting device can thus be reduced in sizeand complexity, and constant monitoring is possible. The powerconsumption of the whole system also can be reduced.

Additional features and advantages are described herein, and will beapparent from the following Detailed Description and the figures.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1A is a schematic partial cross sectional view of a thermoelectricgenerator of Example 1; FIG. 1B is a diagram schematically representingthe temperature (T_(A)) of a first support member and the temperature(T_(B)) of a second support member, changes in temperature differencebetween these temperatures (ΔT=T_(B)−T_(A)), and changes in voltage V₁₋₂between a first output section and a second output section.

FIG. 2A is a schematic partial cross sectional view of a thermoelectricgenerator of Example 2; FIG. 2B is a diagram representing thetemperature (T_(A)) of a first support member and the temperature(T_(B)) of a second support member, changes in temperature differencebetween these temperatures (ΔT=T_(B)−T_(A)), and changes in voltage V₁₋₂between a first output section and a second output section.

FIG. 3A is a schematic partial cross sectional view of a thermoelectricgenerator of Example 3; FIG. 3B is a diagram representing thetemperature (T_(A)) of a first support member and the temperature(T_(B)) of a second support member, changes in temperature differencebetween these temperatures (ΔT=T_(B)−T_(A)), and changes in voltage V₁₋₂between a first output section and a second output section.

FIG. 4 is a schematic partial plan view of a thermoelectric generator ofExample 4.

FIGS. 5A to 5E are schematic partial cross sectional views of thethermoelectric generator of Example 4 illustrated in FIG. 4, at arrowsA-A, B-B, C-C, D-D, and E-E, respectively.

FIGS. 6A and 6B are schematic partial cross sectional views of athermoelectric generator of Example 5.

FIG. 7 is a diagram schematizing the temperature (T_(A)) of a firstsupport member and the temperature (T_(B)) of a second support member ofExample 5, changes in temperature difference between these temperatures(ΔT=T_(B)−T_(A)), changes in voltage V₁₋₂ between a first output sectionand a second output section, and changes in V₃₋₄ between a third outputsection and a fourth output section.

FIGS. 8A and 8B are schematic partial cross sectional views of athermoelectric generator of Example 6.

FIG. 9 is a diagram schematizing the temperature (T_(A)) of a firstsupport member and the temperature (T_(B)) of a second support member ofExample 6, changes in temperature difference between these temperatures(ΔT=T_(B)−T_(A)), changes in voltage V₁₋₂ between a first output sectionand a second output section, and changes in V₃₋₄ between a third outputsection and a fourth output section.

FIGS. 10A and 10B are schematic partial cross sectional views of athermoelectric generator of Example 7.

FIG. 11 is a diagram schematizing the temperature (T_(A)) of a firstsupport member and the temperature (T_(B)) of a second support member ofExample 7, changes in temperature difference between these temperatures(ΔT=T_(B)−T_(A)), changes in voltage V₁₋₂ between a first output sectionand a second output section, and changes in V₃₋₄ between a third outputsection and a fourth output section.

FIGS. 12A and 12B are schematic partial cross sectional views of athermoelectric generator of Example 8.

FIG. 13 is a diagram schematizing the temperature (T_(A)) of a firstsupport member and the temperature (T_(B)) of a second support member ofExample 8, changes in temperature difference between these temperatures(ΔT=T_(B)−T_(A)), changes in voltage V₁₋₂ between a first output sectionand a second output section, and changes in V₃₋₄ between a third outputsection and a fourth output section.

FIGS. 14A and 14B are schematic partial cross sectional views of athermoelectric generator of Example 9.

FIG. 15 is a diagram schematizing the temperature (T_(A)) of a firstsupport member and the temperature (T_(B)) of a second support member ofExample 9, changes in temperature difference between these temperatures(ΔT=T_(B)−T_(A)), changes in voltage V₁₋₂ between a first output sectionand a second output section, and changes in V₃₋₄ between a third outputsection and a fourth output section.

FIGS. 16A and 16B are schematic partial cross sectional views of athermoelectric generator of Example 10.

FIGS. 17A to 17C are circuit diagrams representing examples of rectifiercircuits; FIG. 17D is a conceptual view representing an applicationexample of a thermoelectric generator of an embodiment.

FIG. 18 is a graph representing the simulation result of changes in thetemperature difference ΔT (=T_(B)−T_(A)) between the temperature T_(B)of a second support member and the temperature T_(A) of a first supportmember in response to assumed sinusoidal temperature changes in theatmosphere.

FIG. 19 is a graph representing the simulation results for ΔT as afunction of τ₁ at different values of parameter ω with τ₂ held constantat 0.1.

DETAILED DESCRIPTION

The following describes the present embodiments based on Examples withreference to the accompanying drawings. It should be noted that theembodiments are not limited to the following Examples, and the numericalvalues and materials presented in the following Examples areillustrative. Descriptions will be given in the following order.

1. Overall descriptions of thermoelectric generators and thermoelectricgeneration methods of embodiments

2. Example 1 (thermoelectric generator and thermoelectric generationmethod according to First Embodiment)

3. Example 2 (thermoelectric generation method according to SecondEmbodiment, and thermoelectric generator according to First Embodiment)

4. Example 3 (thermoelectric generator and thermoelectric generationmethod according to Third Embodiment)

5. Example 4 (variation of Example 3)

6. Example 5 (thermoelectric generation method according to FourthEmbodiment A)

7. Example 6 (thermoelectric generation method according to FourthEmbodiment B, and thermoelectric generator according to FourthEmbodiment)

8. Example 7 (variation of Example 6)

9. Example 8 (thermoelectric generation method according to FifthEmbodiment A)

10. Example 9 (thermoelectric generation method according to FifthEmbodiment B, and thermoelectric generator according to FifthEmbodiment)

11. Example 10 (variation of Example 9)

12. Example 11 (variation of Example 2)

13. Example 12 (electrical signal detecting method according to FirstEmbodiment, and electrical signal detecting device according to anembodiment)

14. Example 13 (electrical signal detecting method according to SecondEmbodiment)

15. Example 14 (electrical signal detecting method according to ThirdEmbodiment)

16. Example 15 (electrical signal detecting method according to FourthEmbodiment A)

17. Example 16 (electrical signal detecting method according to FourthEmbodiment B)

18. Example 17 (electrical signal detecting method according to FifthEmbodiment A)

19. Example 18 (electrical signal detecting method according to FifthEmbodiment B), and other

[Overall Descriptions of Thermoelectric Generator and ThermoelectricGeneration Method of Embodiments]

The following concerns a thermoelectric generator for the thermoelectricgeneration method according to Fourth Embodiment A, and for theelectrical signal detecting method according to Fourth Embodiment A; thethermoelectric generator according to Fourth Embodiment, and theelectrical signal detecting device of the embodiment using thethermoelectric generator according to Fourth Embodiment.

The thermoelectric generator according to Fourth Embodiment A or thelike may be adapted so that:

the first output section is connected to an end portion of firstthermoelectric conversion member on the first support member side;

the second output section is connected to an end portion of the secondthermoelectric conversion member on the first support member side;

a third output section is connected to an end portion of the thirdthermoelectric conversion member on the second support member side; and

the fourth output section is connected to an end portion of the fourththermoelectric conversion member on the second support member side.

The following concerns a thermoelectric generator for the thermoelectricgeneration method according to Fourth Embodiment B, and for theelectrical signal detecting method according to Fourth Embodiment B; thethermoelectric generator according to Fourth Embodiment; and theelectrical signal detecting device of the embodiment using thethermoelectric generator according to Fourth Embodiment.

The thermoelectric generator according to Fourth Embodiment B or thelike may be adapted so that:

the first output section is connected to an end portion of the firstthermoelectric conversion member on the first support member side;

the second output section is connected to an end portion of the secondthermoelectric conversion member on the first support member side;

the third output section is connected to an end portion of the thirdthermoelectric conversion member on the first support member side; and

the fourth output section is connected to an end portion of the fourththermoelectric conversion member on the first support member side.

In the thermoelectric generator of such a preferred configurationaccording to Fourth Embodiment B or the like, it is preferable that therelation τ_(TE1)≠τ_(TE2) is established, where τ_(TE1) is the thermalresponse time constant of the first thermoelectric conversion element,and τ_(TE2) is the thermal response time constant of the secondthermoelectric conversion element.

In this case, the thermoelectric generator may be adapted so that:

the first thermoelectric conversion member has a first surface of areaS₁₁, and a second surface of area S₁₁ (S₁₁>S₁₂);

the second thermoelectric conversion member has a first surface of areaS₂₁, and a second surface of area S₂₂ (S₂₁>S₂₂);

the third thermoelectric conversion member has a first surface of areaS₃₁, and a second surface of area S₃₂ (S₃₁<S₃₂); and

the fourth thermoelectric conversion member has a first surface of areaS₄₁, and a second surface of area S₄₂ (S₄₁<S₄₂), and that:

the first surfaces of the first thermoelectric conversion member and thesecond thermoelectric conversion member are in contact with the firstsupport member;

the second surfaces of the first thermoelectric conversion member andthe second thermoelectric conversion member are in contact with thesecond support member;

the first surfaces of the third thermoelectric conversion member and thefourth thermoelectric conversion member are in contact with the firstsupport member; and

the second surfaces of the third thermoelectric conversion member andthe fourth thermoelectric conversion member are in contact with thesecond support member.

The first thermoelectric conversion member, the second thermoelectricconversion member, the third thermoelectric conversion member, and thefourth thermoelectric conversion member of such configurations may havethe shape of, for example, truncated cones, more specifically, truncatedtriangular pyramids, truncated quadrangular pyramids, truncatedhexagonal pyramids, or truncated circular cones.

In this case, the relations VL₁≠VL₃, and VL₂≠VL₄ may be established,where VL₁ is the volume of the first thermoelectric conversion member,VL₂ is the volume of the second thermoelectric conversion member, VL₃ isthe volume of the third thermoelectric conversion member, and VL₄ is thevolume of the fourth thermoelectric conversion member.

The first thermoelectric conversion member, the second thermoelectricconversion member, the third thermoelectric conversion member, and thefourth thermoelectric conversion member of such configurations may be,for example, columnar in shape, more specifically, triangular columns,quadrangular columns, hexagonal columns, or circular columns.Preferably, VL₁≠VL₂, and VL₃≠VL₄.

The following concerns a thermoelectric generator for the thermoelectricgeneration method according to Fifth Embodiment A, and for theelectrical signal detecting method according to Fifth Embodiment A; thethermoelectric generator according to Fifth Embodiment; and theelectrical signal detecting device according to the embodiment using thethermoelectric generator according to Fifth Embodiment.

The thermoelectric generator according to Fifth Embodiment A or the likemay be adapted so that:

the first output section is connected to an end portion of the firstthermoelectric conversion member B;

the second output section is connected to an end portion of the secondthermoelectric conversion member A;

the third output section is connected to an end portion of the thirdthermoelectric conversion member A; and

the fourth output section is connected to an end portion of the fourththermoelectric conversion member B.

Alternatively, the following concerns a thermoelectric generator for thethermoelectric generation method according to Fifth Embodiment B, andfor the electrical signal detecting method according to Fifth EmbodimentB; the thermoelectric generator according to Fifth Embodiment; and theelectrical signal detecting device of the embodiment using thethermoelectric generator according to Fifth Embodiment.

The thermoelectric generator of the invention according to FifthEmbodiment B or the like may be adapted so that:

the first output section is connected to an end portion of the firstthermoelectric conversion member B;

the second output section is connected to an end portion of the secondthermoelectric conversion member A;

the third output section is connected to an end portion of the thirdthermoelectric conversion member B; and

the fourth output section is connected to an end portion of the fourththermoelectric conversion member A.

In the thermoelectric generator of such a preferred configurationaccording to Fifth Embodiment B or the like, it is preferable that therelations τ_(TE1)≠τ_(TE3), and τ_(TE2)≠τ_(TE4) are established, whereτ_(TE1) is the thermal response time constant of the firstthermoelectric conversion element, τ_(TE2) is the thermal response timeconstant of the second thermoelectric conversion element, τ_(TE3) is thethermal response time constant of the third thermoelectric conversionelement, and τ_(TE4) is the thermal response time constant of the fourththermoelectric conversion element.

In this case, the thermoelectric generator may be adapted so that therelations VL₁≠VL₃, and VL₂≠VL₄ are established, where VL₁ is the volumeof the first thermoelectric conversion element, VL₂ is the volume of thesecond thermoelectric conversion element, VL₃ is the volume of the thirdthermoelectric conversion element, and VL₄ is the volume of the fourththermoelectric conversion element.

Alternatively, the relations S₁₂≠S₃₂, and S₂₁≠S₄₁, or the relationsS₁₂≠S₂₁, and S₃₂≠S₄₁ may be established, where S₁₂ is the area of theportion of the first thermoelectric conversion member A in contact withthe second support member, S₂₁ is the area of the portion of the secondthermoelectric conversion member B in contact with the first supportmember, S₃₂ is the area of the portion of the third thermoelectricconversion member A in contact with the second support member, and S₄₁is the area of the portion of the fourth thermoelectric conversionmember B in contact with the first support member.

The number of thermoelectric conversion elements forming thethermoelectric generator is essentially arbitrary, and may be decidedaccording to the thermoelectric output required of the thermoelectricgenerator in the thermoelectric generation methods according to First toFifth Embodiments B, the electrical signal detecting methods accordingto First to Fifth Embodiments B, the thermoelectric generators accordingto First to Fifth Embodiments, and the electrical signal detectingdevice of the embodiment, including the various preferred configurationsdescribed above.

The thermal response time constant τ is determined by the density ρ,specific heat c, and heat-transfer coefficient h of the materialsforming the support member, the thermoelectric conversion element, andthe thermoelectric conversion member, and the volume VL and area S ofthe support member, the thermoelectric conversion element, and thethermoelectric conversion member. The value of thermal response timeconstant increases with use of materials of large density and specificheat and small heat-transfer coefficient, and of large volume and smallarea. The thermal response time constant τ can be determined by thefollowing equation (1).τ=(ρ·c/h)×(V/S)  (1)

In the present embodiment, the thermal response time constant can bemeasured by creating step-like temperature changes to one end of thethermoelectric generator, and by monitoring the resulting temperaturetransient response with, for example, an infrared thermometer.Alternatively, the thermal response time constant can be measured bymeasuring a temperature transition with a thermocouple of sufficientlyfast thermal time constant attached to the support member. Further, thethermal response time constant of the thermoelectric conversion elementcan be obtained by estimating the temperature difference between theupper and lower terminals of the thermoelectric conversion elementthrough monitoring of the output waveform of the thermoelectricgenerator upon creating similar temperature changes, and by measuringthe time for this output voltage to vary from the point of maximumvoltage to minimum voltage.

The temperature T_(SM) of the support member can be determined from thefollowing equation (2).T _(amb) =T _(SM)+τ_(SM)×(dT _(SM) /dt)  (2),

where T_(amb) is the temperature of the atmosphere in which thethermoelectric generator is placed, and τ_(SM) is the thermal responsetime constant of the support member.

It is assumed here that temperature changes of the atmospherictemperature T_(amb) are sinusoidal as represented by the followingequation (3).T _(amb) =ΔT _(amb)×sin(ω·t)+A  (3),

where ΔT_(amb) is the amplitude of the temperature change of atmospherictemperature T_(amb), ω is the angular velocity represented by a valueobtained by dividing 2π by an inverse of temperature change cycle (TM),and A is a constant.

The thermal responses T₁ and T₂ of the support members having thermalresponse time constants τ₁ and τ₂ for such temperature changes ofatmospheric temperature T_(amb) can be represented by the followingequations (4-1) and (4-2).T ₁ =ΔT _(amb)(1+τ₁ ²ω²)⁻¹×sin(ω·t+k ₁)+B ₁  (4-1)T ₂ =ΔT _(amb)(1+τ₂ ²ω²)⁻¹×sin(ω·t+k ₂)+B ₂  (4-2),where sin(k₁)=(τ₁·ω)·(1+τ₁ ²ω²)⁻¹,cos(k₁)=(1+τ₁ ²ω²)⁻¹,sin(k₂)=(τ₂·ω)·(1+τ₂ ²ω²)⁻¹,cos(k₂)=(1+τ₂ ²ω²)⁻¹,k₁ and k₂ represent phase lags, andB₁ and B₂ are the center temperatures of temperature change.

Thus, the temperature difference (ΔT=T_(B)−T_(A)) between thetemperature (T_(A)) of the first support member and the temperature(T_(B)) of the second support member can be approximated from thefollowing equation (5).ΔT=[ΔT _(amb)·ω(τ₁−τ₂)]×(1+τ₁ ²ω²)⁻¹×(1+τ₂ ²ω²)⁻¹×sin(ω·t+φ)+C  (5),where sin(φ)=N(M²+N²)⁻¹,cos(φ)=M(M²+N²)⁻¹,C=B₁−B₂,M=ω(τ₁ ²−τ₂ ²),N=τ₂(1+τ₁ ²ω²)−τ₁(1+τ₂ ²ω²)

FIG. 19 represents the simulation results for ΔT as a function of τ₁ atdifferent values of parameter ω with τ₂ held constant at 0.1. The valuesof ΔT have been normalized so that the maximum value is 1. The symbols Ato O in FIG. 19 each represent temperature change cycle TM, as follows.

Sym- TM Sym- TM Sym- TM Sym- TM bol (min) bol (min) bol (min) bol (min)A 1,440 B 720 C 360 D 180 E 90 F 30 G 10 H 5 I 1 J 0.5 K 0.1 L 0.05 M0.01 N 0.001 O 0.0001

According to Fourth Embodiment A, Fourth Embodiment B, Fifth EmbodimentA, and Fifth Embodiment B, the arrangement of the first thermoelectricconversion element and the second thermoelectric conversion element isessentially arbitrary. For example, the following arrangements arepossible. The first thermoelectric conversion element and the secondthermoelectric conversion element may be alternately arranged in asingle row. A set of a plurality of first thermoelectric conversionelements, and a set of a plurality of second thermoelectric conversionelements may be alternately arranged in a single row. A single row offirst thermoelectric conversion elements may be adjoined by a single rowof second thermoelectric conversion elements. Plural rows of firstthermoelectric conversion elements may be adjoined by plural rows ofsecond thermoelectric conversion elements. The thermoelectric generatormay be divided into a plurality of regions, and a plurality of firstthermoelectric conversion elements or a plurality of secondthermoelectric conversion elements may be arranged in each region.

In the present embodiment, the thermoelectric conversion member may beformed using known materials. Examples include: bismuth.tellurium-basedmaterials (specifically, for example, Bi₂Te₃, Bi₂Te_(2.85)Se_(0.15));bismuth.tellurium.antimony-based materials; antimony.tellurium-basedmaterials (specifically, for example, Sb₂Te₃); thallium.tellurium-basedmaterials; bismuth.selenium-based materials (specifically, for example,Bi₂Se₃); lead.tellurium-based materials; tin.tellurium-based materials;germanium.tellurium-based materials; Pb_(1-x)Sn_(x)Te compounds;bismuth.antimony-based materials; zinc.antimony-based materials(specifically, for example, Zn₄Sb₃); cobalt.antimony-based materials(specifically, for example, CoSb₃); iron.cobalt.antimony-basedmaterials; silver.antimony.tellurium-based materials (specifically, forexample, AgSbTe₂); TAGS (Telluride of Antimony, Germanium and Silver)compounds; Si—Ge-based materials; silicide-based materials [Fe—Si-basedmaterials (specifically, for example, β-FeSi₂), Mn—Si-based materials(specifically, for example, MnSi₂), Cr—Si-based materials (specifically,for example, CrSi₂), Mg—Si-based materials (specifically, for example,Mg₂Si)]; skutterudite-based materials [MX₃ compounds (M is Co, Rh, orIr, and X is P, As, or Sb), and RM′₄X₁₂ compounds (R is La, Ce, Eu, Yb,or the like, and M′ is Fe, Ru, or Os)]; boron compounds [specifically,for example, MB₆ (M is alkali earth metal of Ca, Sr, or Ba, andrare-earth metal such as Y)]; Si-based materials; Ge-based materials;clathrate compounds; Heusler compounds; half-Heusler compounds;rare-earth Kondo semiconductor materials; transition metal oxide-basedmaterials (specifically, for example, Na_(x)CoO₂, NaCo₂O₄, Ca₃Co₄O₉);zinc oxide-based materials; titanium oxide-based materials; cobaltoxide-based materials; SrTiO₃; organic thermoelectric convertingmaterials (specifically, for example, polythiophene, polyaniline);Chromel® alloys; constantan, Alumel® alloys; TGS (triglycine sulfate);PbTiO₃; Sr_(0.5)Ba_(0.5)Nb₂O₆; PZT; BaO—TiO₂-based compounds, tungstenbronze (A_(x)BO₃); 15 perovskite-based materials; 24 perovskite-basedmaterials; BiFeO₃; and Bi-layered perovskite-based materials. Thematerial of the thermoelectric conversion member may deviate fromstoichiometric composition. Of these materials, it is preferable to usebismuth.tellurium-based materials and bismuth.tellurium.antimony-basedmaterials in combination. More specifically, it is preferable to use,for example, bismuth.tellurium.antimony-based materials for the firstthermoelectric conversion member, the third thermoelectric conversionmember, the first thermoelectric conversion member A, the secondthermoelectric conversion member A, the third thermoelectric conversionmember A, and the fourth thermoelectric conversion member A, and use,for example, bismuth.tellurium-based materials for the secondthermoelectric conversion member, the fourth thermoelectric conversionmember, the first thermoelectric conversion member B, the secondthermoelectric conversion member B, the third thermoelectric conversionmember B, and the fourth thermoelectric conversion member B. In thiscase, the first thermoelectric conversion member, the thirdthermoelectric conversion member, the first thermoelectric conversionmember A, the second thermoelectric conversion member A, the thirdthermoelectric conversion member A, and the fourth thermoelectricconversion member A behave as p-type semiconductors, and the secondthermoelectric conversion member, the fourth thermoelectric conversionmember, the first thermoelectric conversion member B, the secondthermoelectric conversion member B, the third thermoelectric conversionmember B, and the fourth thermoelectric conversion member B behave asn-type semiconductors. The materials of the first thermoelectricconversion member and the second thermoelectric conversion member mayboth have the Seebeck effect, or only one of these materials may havethe Seebeck effect. Similarly, the materials of the third thermoelectricconversion member and the fourth thermoelectric conversion member mayboth have the Seebeck effect, or only one of these materials may havethe Seebeck effect. The same is the case for the combination of thefirst thermoelectric conversion member A and the first thermoelectricconversion member B, the combination of the second thermoelectricconversion member A and the second thermoelectric conversion member B,the combination of the third thermoelectric conversion member A and thethird thermoelectric conversion member B, and the combination of thefourth thermoelectric conversion member A and the fourth thermoelectricconversion member B.

Examples of methods of manufacture of the thermoelectric conversionmembers and thermoelectric conversion elements, and examples of methodsfor rendering desired shapes to the thermoelectric conversion member andthe thermoelectric conversion element include: cutting the ingot of thematerial forming the thermoelectric conversion member, etching thematerial of the thermoelectric conversion member, molding with a mold,deposition by plating, a combination of PVD or CVD method with apatterning technique, and a liftoff method.

Examples of materials of the first support member and the second supportmember include: fluororesin; epoxy resin; acrylic resin; polycarbonateresin; polypropylene resin; polystyrene resin; polyethylene resin;thermoset elastomer; thermoplastic elastomer (silicon rubber, ethylenerubber, propylene rubber, chloroprene rubber), latent heat storagematerial exemplified by normal paraffin, chemical heat storage material,vulcanized rubber (natural rubber); glass; ceramic (for example, Al₂O₃,MgO, BeO, MN, SiC, TiO₂, earthenware, porcelain); carbon material suchas diamond-like carbon (DLC) and graphite; wood; various metals [forexample, copper (Cu), aluminum (Al), silver (Ag), gold (Au), chromium(Cr), iron (Fe), magnesium (Mg), nickel (Ni), silicon (Si), tin (Sn),tantalum (Ta), titanium (Ti), tungsten (W), antimony (Sb), bismuth (Bi),tellurium (Te), and selenium (Se)]; alloys of these metals; and coppernanoparticles. These materials may be appropriately selected andcombined to form the first support member and the second support member.For improved heat-transfer efficiency, for example, a fin or a heatsinkmay be attached to the outer surfaces of the first support member andthe second support member, or the outer surfaces of the first supportmember and the second support member may be roughened or provided withirregularities.

The latent heat storage material is a material which stores latent heatexchanged with the outside at the time of its change of phase or phasetransition as thermal energy. The above-mentioned normal paraffin (forexample, n-tetradecane, n-pentadecane, n-hexadecane, n-heptadecane,n-octadecane, n-nonadecane, n-icosane and the like) causes change ofphase even at room temperature according to the composition thereof. Byusing such latent heat storage material, as a heat storage, as the firstsupport member or the second support member or a part of the firstsupport member or the second support member, a structure with largerheat capacity can be implemented in a small volume. Accordingly, thethermoelectric conversion element in the thermoelectric generator can beminiaturized and low-profiled. Further, since the latent heat storagematerial hardly changes in temperature, it can be used as a materialconstituting the thermoelectric conversion element receiving temperaturefluctuation in a long cycle. For example, a heat of fusion of epoxyresin is 2.2 kj/kg, whereas a heat of fusion of normal paraffin having amelting point of 25° C. is 85 kj/kg. Accordingly, normal paraffin canstore heat 40 times higher than that of epoxy resin. The chemical heatstorage material utilizes heat of chemical reaction of the material andexamples thereof include Ca(OH)₂/CaO₂+H₂ and Na₂S+5H₂O.

The serial electrical connection between the first thermoelectricconversion member and the second thermoelectric conversion member,between the third thermoelectric conversion member and the fourththermoelectric conversion member, between the first thermoelectricconversion element and the second thermoelectric conversion element, andbetween the third thermoelectric conversion element and the fourththermoelectric conversion element may be made by providing an electrodeon the support member. However, the electrode is not necessarilyrequired. Essentially any material can be used for the electrode, aslong as it is conductive. For example, an electrode structure as thelaminate of a titanium layer, a gold layer, a nickel layer formed inthis order from the thermoelectric conversion member or thermoelectricconversion element side can be formed. In terms of thermoelectricgenerator structure and simplicity, it preferable that part of theelectrode serves as an output section. In some cases, an extension ofthe thermoelectric conversion member or the thermoelectric conversionelement may form the electrode.

The thermoelectric generator may be sealed with, for example, anappropriate resin. The first support member or the second support membermay be provided with the heat storage. The thermoelectric conversionmembers or the thermoelectric conversion elements may be spaced apartwithout any filling, or the space between these members or elements maybe filled with an insulating material.

The present embodiments are applicable to any technical field thatinvolves thermoelectric generation in a temperature-changing atmosphere.Specific examples of such technical fields or devices suited forintegration of the thermoelectric generator include: remote controlunits for operating various devices such as television receivers, videorecorders, and air conditioners; various measurement devices (forexample, measurement devices for monitoring soil conditions, andmeasurement devices for monitoring weather and meteorologicalconditions); remote monitoring devices and remote sensing devices forremote places; portable communications devices; watches; measurementdevices for obtaining biological information such as the bodytemperature, blood pressure, and pulse of the human body, animals,livestock, and pets, and devices for detecting and extracting variouskinds of information based on such biological information; powersupplies for charging secondary batteries; power-generating units usingthe exhaust heat of automobiles; battery-less radio systems; sensornodes of wireless sensor networks; tire pressure monitoring systems(TPMS); remote control units and switches for operating illuminations;systems that operate in synchronism with input signals by usingtemperature information as input signal, or as input signal and energysource; and power supplies for portable music players and hearing aids,and for the noise canceling system of portable music players. Thepresent invention is very suitable for places where reinstallation of apower-generating unit is difficult once it has been installed, or inplaces where placement of wires or interconnections is physicallydifficult. When attached to machines or constructions, the electricalsignal detecting device can be used to detect abnormalities based oncyclic temperature changes created in the machine or construction.Further, the electrical signal detecting device may be used toself-generate power by being attached to keys or cellular phones, inorder to construct a system in which the positional information of theseitems can be transmitted intermittently.

Example 1

Example 1 concerns the thermoelectric generator according to FirstEmbodiment, and the thermoelectric generation method according to FirstEmbodiment. FIG. 1A is a schematic partial cross sectional view of thethermoelectric generator of Example 1. FIG. 1B schematically representsthe temperature (T_(A)) of the first support member, and the temperature(T_(B)) of the second support member; changes in temperature differencebetween these temperatures (ΔT=T_(B)−T_(A)); and changes in voltage V₁₋₂between the first output section and the second output section. Notethat, even though the drawings representing the respective Examples showfour or eight thermoelectric conversion elements or thermoelectricconversion members, the number of thermoelectric conversion elements orthermoelectric conversion members is not limited thereto.

The thermoelectric generator of Example 1 or Example 2 below includes:

(A) a first support member 11;

(B) a second support member 12 disposed opposite the first supportmember 11;

(C) a thermoelectric conversion element disposed between the firstsupport member 11 and the second support member 12; and

(D) a first output section 41 and a second output section 42 connectedto the thermoelectric conversion element.

The thermoelectric conversion element of Example 1 or Example 2 belowincludes:

(C-1) a first thermoelectric conversion member 21A or 21B disposedbetween the first support member 11 and the second support member 12;and

(C-2) a second thermoelectric conversion member 22A or 22B disposedbetween the first support member 11 and the second support member 12,and that is made of material different from the material of the firstthermoelectric conversion member 21A or 21B, and is electricallyconnected in series to the first thermoelectric conversion member 21A or21B.

More specifically, in the thermoelectric generator of Example 1 orExample 2 below, the first thermoelectric conversion member 21A or 21Band the second thermoelectric conversion member 22A or 22B areelectrically connected in series via a wire 32 provided on the secondsupport member 12, and the second thermoelectric conversion member 22Aor 22B and the first thermoelectric conversion member 21A or 21B areelectrically connected in series via a wire 31 provided on the firstsupport member 11. The first output section 41 is connected to an endportion of the first thermoelectric conversion member 21A or 21B on thefirst support member side. The second output section 42 is connected toan end portion of the second thermoelectric conversion member 22A or 22Bon the first support member side.

The first support member 11 is formed of Al₂O₃, and the second supportmember 12 is formed of epoxy resin. The first thermoelectric conversionmember, or the third thermoelectric conversion member, the firstthermoelectric conversion member A, the second thermoelectric conversionmember A, the third thermoelectric conversion member A, and the fourththermoelectric conversion member A below are formed ofbismuth.tellurium.antimony of p-type conductivity. The secondthermoelectric conversion member, or the fourth thermoelectricconversion member, the first thermoelectric conversion member B, thesecond thermoelectric conversion member B, the third thermoelectricconversion member B, and the fourth thermoelectric conversion member Bare formed of bismuth.tellurium of n-type conductivity. The first outputsection 41, the second output section 42, and the wires 31 and 32 have amultilayer structure of a titanium layer, a gold layer, and a nickellayer, from the support member side. The bonding between thethermoelectric conversion member and the wire may be made using a knownbonding technique. The Seebeck coefficient of the first thermoelectricconversion member or first thermoelectric conversion element is SB₁, theSeebeck coefficient of the second thermoelectric conversion member orsecond thermoelectric conversion element is SB₂, the Seebeck coefficientof the third thermoelectric conversion member or third thermoelectricconversion element is SB₃, and the Seebeck coefficient of the fourththermoelectric conversion member or fourth thermoelectric conversionelement is SB₄. The same applies to Examples 2 to 10 below.

In the thermoelectric generator of Example 1, the area of first surface21A₁ of the first thermoelectric conversion member 21A in contact withthe first support member 11 is S₁₁, the area of second surface 21A₂ ofthe first thermoelectric conversion member 21A in contact with thesecond support member 12 is S₁₂ (S₁₁>S₁₂), the area of first surface22A₁ of the second thermoelectric conversion member 22A in contact withthe first support member 11 is S₂₁, and the area of second surface 22A₂of the second thermoelectric conversion member 22A in contact with thesecond support member 12 is S₂₂ (S₂₁>S₂₂). The first support member 11and the second support member 12 have thermal response time constantsτ_(SM1) and τ_(SM2), respectively, which are related to each other byτ_(SM1)>τ_(SM2). In Example 1, S₁₂≠S₂₂. The first thermoelectricconversion member 21A and the second thermoelectric conversion member22A have the shape of a truncated cone, more specifically, a truncatedquadrangular pyramid.

In the thermoelectric generation method of Example 1 or Example 2 below,the thermoelectric generator is placed in a temperature-changingatmosphere. When the temperature of the second support member 12 ishigher than the temperature of the first support member 11, the currentthat is generated by the temperature difference between the firstsupport member 11 and the second support member 12, and that flows fromthe second thermoelectric conversion member 22A or 22B to the firstthermoelectric conversion member 21A or 21B is drawn to outside usingthe first output section 41 as the positive terminal (plus terminal),and the second output section 42 as the negative terminal (minusterminal). In this case, because alternate current flows between thefirst output section 41 and the second output section 42, the currentmay be converted to direct current using a known half-wave rectifiercircuit, followed by smoothing. When the temperature of the firstsupport member 11 is higher than the temperature of the second supportmember 12, the current that is generated by the temperature differencebetween the first support member 11 and the second support member 12,and that flows from the first thermoelectric conversion member 21A or21B to the second thermoelectric conversion member 22A or 22B can bedrawn to outside using the second output section 42 as the positiveterminal, and the first output section 41 as the negative terminal. Inthis case, the alternate current may be converted to direct currentusing a known full-wave rectifier circuit, followed by smoothing.

Because τ_(SM1)>τ_(SM2), the temperature T_(B) of the second supportmember 12 of the thermoelectric generator placed in atemperature-changing atmosphere (atmospheric temperature T_(amb) at timeindicated by ellipsoid A in FIG. 1B) quickly becomes the atmospherictemperature T_(amb), or a temperature near T_(amb). On the other hand,because τ_(SM1)>τ_(SM2), the temperature T_(A) of the first supportmember 11 varies by lagging behind the temperature change of the secondsupport member 12. As a result, a temperature difference ΔT(=T_(B)−T_(A)) occurs between the temperature T_(A) (<T_(amb)) of thefirst support member 11 and the temperature T_(B) (=T_(amb)) of thesecond support member 12. As a rule, the relation T₁₂=T₂₂>T₁₁=T₂₁ isestablished, where T₁₁ is the temperature in the vicinity of the firstsurface 21A₁ of the first thermoelectric conversion member 21A incontact with the first support member 11, T₁₂ is the temperature in thevicinity of the second surface 21A₂ of the first thermoelectricconversion member 21A in contact with the second support member 12, T₂₁is the temperature in the vicinity of the first surface 22A₁ of thesecond thermoelectric conversion member 22A in contact with the firstsupport member 11, and T₂₂ is the temperature in the vicinity of thesecond surface 22A₂ of the second thermoelectric conversion member 22Ain contact with the second support member 12. The electromotive forceEMF by a single thermoelectric conversion element can be determined byEMF=T ₁₂ ×SB ₁ −T ₂₁ ×SB ₂.

It is assumed here that the temperature change in the atmosphere issinusoidal, and that the difference ΔT_(amb) between the maximumtemperature and the minimum temperature of the temperature change is 2°C. The temperature change cycle (TM=2π/ω) is assumed to be 10 minutes.FIG. 18 represents the simulation result of changes in the temperaturedifference ΔT (=T_(B)−T_(A)) between the temperature T_(B) of the secondsupport member 12 and the temperature T_(A) of the first support member11 in response to such temperature changes. In FIG. 18, the curve Brepresents changes in temperature T_(B) of the second support member 12,and the curve A represents changes in temperature T_(A) of the firstsupport member 11.

Example 2

Example 2 concerns the thermoelectric generator according to SecondEmbodiment, and the thermoelectric generation method according to SecondEmbodiment. FIG. 2A is a schematic partial cross sectional view of thethermoelectric generator of Example 2. FIG. 2B schematically representsthe temperature (T_(A)) of the first support member, and the temperature(T_(B)) of the second support member; changes in temperature differencebetween these temperatures (ΔT=T_(B)−T_(A)); and changes in voltage V₁₋₂between the first output section and the second output section.

Example 2 differs from Example 1 in that the first thermoelectricconversion member 21B and the second thermoelectric conversion member22B are columnar in shape, specifically, quadrangular columns. Further,in this Example, the relations τ_(SM1)>τ_(SM2), and VL₁≠VL₂(specifically, VL₁<VL₂ in Example 2) are established, where VL₁ is thevolume of the first thermoelectric conversion member 21B, VL₂ is thevolume of the second thermoelectric conversion member 22B, τ_(SM1) isthe thermal response time constant of the first support member 11, andτ_(SM2) is the thermal response time constant of the second supportmember 12.

Because τ_(SM1)>τ_(SM2), as in Example 1, the temperature T_(B) of thesecond support member 12 of the thermoelectric generator placed in atemperature-changing atmosphere (atmospheric temperature T_(amb) at timeindicated by ellipsoid A in FIG. 2B) quickly becomes the atmospherictemperature T_(amb), or a temperature near T_(amb). On the other hand,because τ_(SM1)>τ_(SM2), the temperature T_(A) of the first supportmember 11 varies by lagging behind the temperature change of the secondsupport member 12. As a result, a temperature difference ΔT(=T_(B)−T_(A)) occurs between the temperature T_(A) (<T_(amb)) of thefirst support member 11 and the temperature T_(B) (=T_(amb)) of thesecond support member 12. Provided that VL₁<VL₂, the relationsT₁₂>T₂₂>T₁₁>T₂₁, and T₁₂−T₁₁>T₂₂−T₂₁ are established, where T₁₁ is thetemperature in the vicinity of the first surface 21B₁ of the firstthermoelectric conversion member 21B in contact with the first supportmember 11, T₁₂ is the temperature in the vicinity of the second surface21B₂ of the first thermoelectric conversion member 21B in contact withthe second support member 12, T₂₁ is the temperature in the vicinity ofthe first surface 22B₁ of the second thermoelectric conversion member22B in contact with the first support member 11, and T₂₂ is thetemperature in the vicinity of the second surface 22B₂ of the secondthermoelectric conversion member 22B in contact with the second supportmember 12. The electromotive force EMF by a single thermoelectricconversion element can be determined by EMF=(T₁₂−T₁₁)×SB₁+(T₂₁−T₂₂)×SB₂.

Example 3

Example 3 concerns the thermoelectric generator of Third Embodiment, andthe thermoelectric generation method according to Third Embodiment. FIG.3A is a schematic partial cross sectional view of the thermoelectricgenerator of Example 3. FIG. 3B schematically represents the temperature(T_(A)) of the first support member, the temperature (T_(B)) of thesecond support member; changes in temperature difference between thesetemperatures (ΔT=T_(B)−T_(A)); and changes in voltage V₁₋₂ between thefirst output section and the second output section.

The thermoelectric generator of Example 3 includes:

(A) a first support member 11;

(B) a second support member 12 disposed opposite the first supportmember 11;

(C) a first thermoelectric conversion element 121C disposed between thefirst support member 11 and the second support member 12;

(D) a second thermoelectric conversion element 122C disposed between thefirst support member 11 and the second support member 12; and

(E) a first output section 141 and a second output section 142.

In the thermoelectric generator of Example 3, the first thermoelectricconversion element 121C includes a first thermoelectric conversionmember A-121C_(A) in contact with the second support member 12, and afirst thermoelectric conversion member B-121C_(B) in contact with thefirst support member 11. The first thermoelectric conversion memberA-121C_(A) and the first thermoelectric conversion member B-121C_(B) arein contact with (specifically, laminated with) each other. The secondthermoelectric conversion element 122C includes a second thermoelectricconversion member A-122C_(A) in contact with the first support member11, and a second thermoelectric conversion member B-122C_(B) in contactwith the second support member 12. The second thermoelectric conversionmember A-122C_(A) and the second thermoelectric conversion memberB-122C_(B) are in contact with (specifically, laminated with) eachother.

The first thermoelectric conversion element 121C and the secondthermoelectric conversion element 122C are electrically connected toeach other in series. The first output section 141 is connected to anend portion of the first thermoelectric conversion member B-121C_(B).The second output section 142 is connected to an end portion of thesecond thermoelectric conversion member A-122C_(A). The firstthermoelectric conversion member A-121C_(A) and the secondthermoelectric conversion member B-122C_(B) are electrically connectedto each other via a wire 32 provided on the second support member 12.The second thermoelectric conversion member A-122C_(A) and the firstthermoelectric conversion member B-121C_(B) are electrically connectedto each other via a wire 31 provided on the first support member 11.

The relation τ_(SM1)≠τ_(SM2) is established, where τ_(SM1) is thethermal response time constant of the first support member 11, andτ_(SM2) is the thermal response time constant of the second supportmember 12. The first thermoelectric conversion element 121C and thesecond thermoelectric conversion element 122C are columnar in shape,specifically, quadrangular columns.

In the thermoelectric generation method of Example 3, the thermoelectricgenerator is placed in a temperature-changing atmosphere. When thetemperature of the second support member 12 is higher than thetemperature of the first support member 11, the current that isgenerated due to the temperature difference between the first supportmember 11 and the second support member 12, and that flows from thesecond thermoelectric conversion element 122C to the firstthermoelectric conversion element 121C is drawn to outside using thefirst output section 141 as the positive terminal, and the second outputsection 142 as the negative terminal. In this case, because alternatecurrent flows between the first output section 141 and the second outputsection 142, the current may be converted into direct current using aknown half-wave rectifier circuit, followed by smoothing. When thetemperature of the first support member 11 is higher than thetemperature of the second support member 12, the current that isgenerated due to the temperature difference between the first supportmember 11 and the second support member 12, and that flows from thefirst thermoelectric conversion element 121C to the secondthermoelectric conversion element 122C can be drawn to outside using thesecond output section 142 as the positive terminal, and the first outputsection 141 as the negative terminal. In this case, the alternatecurrent may be converted into direct current using a known full-waverectifier circuit, followed by smoothing.

When τ_(SM1)>τ_(SM2), the temperature T_(B) of the second support member12 of the thermoelectric generator placed in a temperature-changingatmosphere (atmospheric temperature T_(amb) at time indicated byellipsoid A in FIG. 3B) quickly becomes the atmospheric temperatureT_(amb), or a temperature near T_(amb). On the other hand, becauseτ_(SM1)>τ_(SM2), the temperature T_(A) of the first support member 11varies by lagging behind the temperature change of the second supportmember 12. As a result, a temperature difference ΔT (=T_(B)−T_(A))occurs between the temperature T_(A) (<T_(amb)) of the first supportmember 11 and the temperature T_(B) (=T_(amb)) of the second supportmember 12. The relation T₂>T₁ is established, where T₂ is thetemperature in the vicinity of the second surface 121C₂ of the firstthermoelectric conversion element 121C in contact with the secondsupport member 12, and the temperature in the vicinity of the secondsurface 122C₂ of the second thermoelectric conversion element 122C incontact with the second support member 12, and T₁ is the temperature inthe vicinity of the first surface 121C₁ of the first thermoelectricconversion element 121C in contact with the first support member 11, andthe temperature in the vicinity of the first surface 122C₁ of the secondthermoelectric conversion element 122C in contact with the first supportmember 11. The electromotive force EMF by a single pair of thethermoelectric conversion elements 121C and 122C can be determined byEMF=T₂×SB₁−T₁×SB₂.

Example 4

Example 4 is a variation of Example 3. In Example 3, the firstthermoelectric conversion element 121C and the second thermoelectricconversion element 122C are laminated elements, specifically, thelaminate of the first thermoelectric conversion member A-121C_(A) andthe first thermoelectric conversion member B-121C_(B), and the laminateof the second thermoelectric conversion member A-122C_(A) and the secondthermoelectric conversion member B-122C_(B). In Example 4, a firstthermoelectric conversion element 221C and a second thermoelectricconversion element 222C are provided that are horizontally disposedelements. FIG. 4 is a schematic partial plan view of the thermoelectricgenerator of Example 4. FIGS. 5A, 5B, 5C, 5D, and 5E are schematicpartial cross sectional views of the thermoelectric generator of Example4 illustrated in FIG. 4, at arrows A-A, B-B, C-C, D-D, and E-E,respectively. In FIG. 4, the constituting elements of the thermoelectricgenerator are hatched for clarity.

In Example 4, the first thermoelectric conversion element 221C includesa first thermoelectric conversion member A-221C_(A) in contact with thesecond support member 212, and a first thermoelectric conversion memberB-221C_(B) in contact with the first support member 211. The firstthermoelectric conversion member A-221C_(A) and the first thermoelectricconversion member B-221C_(B) are disposed in contact with each otheralong the horizontal direction. The second thermoelectric conversionelement 222C includes a second thermoelectric conversion memberA-222C_(A) in contact with the first support member 211, and a secondthermoelectric conversion member B-222C_(B) in contact with the secondsupport member 212. The second thermoelectric conversion memberA-222C_(A) and the second thermoelectric conversion member B-222C_(B)are disposed in contact with each other along the horizontal direction.More specifically, the first thermoelectric conversion member A-221C_(A)and the first thermoelectric conversion member B-221C_(B) are in contactwith each other via a joint member 213 on their end faces along thehorizontal direction. Similarly, the second thermoelectric conversionmember A-222C_(A) and the second thermoelectric conversion memberB-222C_(B) are in contact with each other via the joint member 213 ontheir end faces along the horizontal direction. The second supportmember 212 is disposed beneath the end portions of the firstthermoelectric conversion member A-221C_(A) and the secondthermoelectric conversion member B-222C_(B), supporting the firstthermoelectric converting member A-221C_(A) and the secondthermoelectric conversion member B-222C_(B). Similarly, the firstsupport member 211 is disposed beneath the end portions of the firstthermoelectric conversion member B-221C_(B) and the secondthermoelectric conversion member A-222C_(A), supporting the firstthermoelectric conversion member B-221C_(B) and the secondthermoelectric conversion member A-222C_(A).

The first thermoelectric conversion element 221C and the secondthermoelectric conversion element 222C are electrically connected toeach other in series. The first output section 241 is connected to anend portion of the first thermoelectric conversion member B-221C_(B).The second output section 242 is connected to an end portion of thesecond thermoelectric conversion member A-222C_(A). The firstthermoelectric conversion member A-221C_(A) and the secondthermoelectric conversion member B-222C_(B) are electrically connectedto each other via a wire 232 provided on the second support member 212.The second thermoelectric conversion member A-222C_(A) and the firstthermoelectric conversion member B-221C_(B) are electrically connectedto each other via a wire 231 provided on the first support member 12.

As in Example 3, the relation τ_(SM1)≠τ_(SM2) is established, whereτ_(SM1) is the thermal response time constant of the first supportmember 211, and τ_(SM2) is the thermal response time constant of thesecond support member 212. The first thermoelectric conversion element221C and the second thermoelectric conversion element 222C are cuboid(tabular) in shape.

In the thermoelectric generation method of Example 4, the thermoelectricgenerator is placed in a temperature-changing atmosphere. When thetemperature of the second support member 212 is higher than thetemperature of the first support member 211, the current that isgenerated due to the temperature difference between the first supportmember 211 and the second support member 212, and that flows from thesecond thermoelectric conversion element 222C to the firstthermoelectric conversion element 221C is drawn to outside using thefirst output section 241 as the positive terminal, and the second outputsection 242 as the negative terminal. In this case, because alternatecurrent flows between the first output section 241 and the second outputsection 242, the current may be converted into direct current using aknown half-wave rectifier circuit, followed by smoothing. When thetemperature of the first support member 211 is higher than thetemperature of the second support member 212, the current that isgenerated by the temperature difference between the first support member211 and the second support member 212, and that flows from the firstthermoelectric conversion element 221C to the second thermoelectricconversion element 222C can be drawn to outside using the second outputsection 242 as the positive terminal, and the first output section 241as the negative terminal. In this case, the alternate current may beconverted to direct current using a known full-wave rectifier circuit,followed by smoothing.

When τ_(SM1)>τ_(SM2), the temperature T_(B) of the second support member212 of the thermoelectric generator placed in a temperature-changingatmosphere (atmospheric temperature T_(amb) at time indicated byellipsoid A in FIG. 3B) quickly becomes the atmospheric temperatureT_(amb), or a temperature near T_(amb). On the other hand, becauseτ_(SM1)>τ_(SM2), the temperature T_(A) of the first support member 211varies by lagging behind the temperature change of the second supportmember 212. As a result, a temperature difference ΔT (=T_(B)−T_(A))occurs between the temperature T_(A) (<T_(amb)) of the first supportmember 211 and the temperature T_(B) (=T_(amb)) of the second supportmember 212. Thus, the relation T₂>T₁ is established, where T₂ is thetemperature in the vicinity of the first thermoelectric conversionmember A-221C_(A) and the second thermoelectric conversion memberB-222C_(B) in contact with the second support member 212, and T₁ is thetemperature in the vicinity of the first thermoelectric conversionmember B-221C_(B) and the second thermoelectric conversion memberA-222C_(A) in contact with the first support member 211. Theelectromotive force EMF by a single pair of the thermoelectricconversion elements 221C and 222C can be determined byEMF=T₂×SB₁−T₁×SB₂.

In some cases, the relations τ_(SM3)≠τ_(SM1), τ_(SM3)≠τ_(SM2), andτ_(SM1)=τ_(SM2) may be established, where τ_(SM3) is the thermalresponse time constant of the joint member 213.

Example 5

Example 5 concerns the thermoelectric generation method according toFourth Embodiment A.

FIGS. 6A and 6B are schematic partial cross sectional views of athermoelectric generator suitable for use in the thermoelectricgeneration method of Example 5. FIG. 7 schematically represents thetemperature (T_(A)) of the first support member and the temperature(T_(B)) of the second support member; changes in temperature differencebetween these temperatures (ΔT=T_(B)−T_(A)); changes in voltage V₁₋₂between the first output section and the second output section; andchanges in voltage V₃₋₄ between the third output section and the fourthoutput section.

The thermoelectric generator of Example 5 or of Examples 6 and 7 belowincludes:

(A) a first support member 11;

(B) a second support member 12 disposed opposite the first supportmember 11;

(C) a first thermoelectric conversion element disposed between the firstsupport member 11 and the second support member 12;

(D) a second thermoelectric conversion element disposed between thefirst support member 11 and the second support member 12; and

(E) a first output section 41, a second output section 42, a thirdoutput section 43, and a fourth output section 44.

The first thermoelectric conversion element includes:

(C-1) a first thermoelectric conversion member 21D, 21E, or 21F disposedbetween the first support member 11 and the second support member 12;

(C-2) a second thermoelectric conversion member 22D, 22E, or 22Fdisposed between the first support member 11 and the second supportmember 12, and that is made of material different from the material ofthe first thermoelectric conversion member 21D, 21E, or 21F, and iselectrically connected to the first thermoelectric conversion member21D, 21E, or 21F in series.

The second thermoelectric conversion element includes:

(D-1) a third thermoelectric conversion member 23D, 23E, or 23F disposedbetween the first support member 11 and the second support member 12;and

(D-2) a fourth thermoelectric conversion member 24D, 24E, or 24Fdisposed between the first support member 11 and the second supportmember 12, and that is made of material different from that of the thirdthermoelectric conversion member 23D, 23E, or 23F, and is electricallyconnected to the third thermoelectric conversion member 23D, 23E, or 23Fin series.

The first output section 41 is connected to the first thermoelectricconversion member 21D, 21E, or 21F. The second output section 42 isconnected to the second thermoelectric conversion member 22D, 22E, or22F. The third output section 43 is connected to the thirdthermoelectric conversion member 23D, 23E, or 23F. The fourth outputsection 44 is connected to the fourth thermoelectric conversion member24D, 24E, or 24F.

More specifically, in Example 5 or Examples 6 and 7 below, the firstthermoelectric conversion member 21D, 21E, or 21F and the secondthermoelectric conversion member 22D, 22E, or 22F are electricallyconnected to each other in series via a wire 31B provided on the secondsupport member 12. The second thermoelectric conversion member 22D, 22E,or 22F and the first thermoelectric conversion member 21D, 21E, or 21Fare electrically connected to each other in series via a wire 31Aprovided on the first support member 11. The third thermoelectricconversion member 23D, 23E, or 23F and the fourth thermoelectricconversion member 24D, 24E, or 24F are electrically connected to eachother in series via a wire 32A provided on the first support member 11.The fourth thermoelectric conversion member 24D, 24E, or 24F and thethird thermoelectric conversion member 23D, 23E, or 23F are electricallyconnected to each other in series via a wire 32B provided on the secondsupport member 12.

The first thermoelectric conversion member 21D has a first surface 21D₁of area S₁₁ and a second surface 21D₂ of area S₁₂ (S₁₁>S₁₂). The secondthermoelectric conversion member 22D has a first surface 22D₁ of areaS₂₁, and a second surface 22D₂ of area S₂₂ (S₂₁>S₂₂). The thirdthermoelectric conversion member 23D has a first surface 23D₁ of areaS₃₁, and a second surface 23D₂ of area S₃₂ (S₃₁<S₃₂). The fourththermoelectric conversion member 24D has a first surface 24D₁ of areaS₄₁, and a second surface 24D₂ of area S₄₂ (S₄₁<S₄₂). The first surfaces21D₁ and 22D₁ of the first thermoelectric conversion member 21D and thesecond thermoelectric conversion member 22D are in contact with thefirst support member 11. The second surfaces 21D₂ and 22D₂ of the firstthermoelectric conversion member 21D and the second thermoelectricconversion member 22D are in contact with the second support member 12.The first surfaces 23D₁ and 24D₁ of the third thermoelectric conversionmember 23D and the fourth thermoelectric conversion member 24D are incontact with the first support member 11. The second surfaces 23D₂ and24D₂ of the third thermoelectric conversion member 23D and the fourththermoelectric conversion member 24D are in contact with the secondsupport member 12. The first thermoelectric conversion member 21D, thesecond thermoelectric conversion member 22D, the third thermoelectricconversion member 23D, and the fourth thermoelectric conversion member24D have the shape of truncated cones, specifically, truncatedquadrangular pyramids. Note that the first to fourth thermoelectricconversion members of the thermoelectric generator of Example 6 belowhave the same configurations as the first to fourth thermoelectricconversion members of the thermoelectric generator of Example 5described above.

The relation τ_(SM1)≠τ_(SM2) is established, where τ_(SM1) is thethermal response time constant of the first support member 11, andτ_(SM2) is the thermal response time constant of the second supportmember 12. Further, the relation τ_(TE1)≠τ_(TE2) is established, whereτ_(TE1) is the thermal response time constant of the firstthermoelectric conversion element, and τ_(TE2) is the thermal responsetime constant of the second thermoelectric conversion element.

The first output section 41 is connected to an end portion of the firstthermoelectric conversion member 21D on the first support member side.The second output section 42 is connected to an end portion of thesecond thermoelectric conversion member 22D on the first support memberside. The third output section 43 is connected to an end portion of thethird thermoelectric conversion member 23D on the second support memberside. The fourth output section 44 is connected to an end portion of thefourth thermoelectric conversion member 24D on the second support memberside. Specifically, the first output section 41 and the second outputsection 42, and the third output section 43 and the fourth outputsection 44 are disposed on different support members.

In the thermoelectric generation method of Example 5, the thermoelectricgenerator is placed in a temperature-changing atmosphere. When thetemperature of the second support member 12 is higher than thetemperature of the first support member 11, the current that isgenerated due to the temperature difference between the first supportmember 11 and the second support member 12, and that flows from thesecond thermoelectric conversion member 22D to the first thermoelectricconversion member 21D is drawn to outside using the first output section41 as the positive terminal, and the second output section 42 as thenegative terminal. On the other hand, when the temperature of the firstsupport member 11 is higher than the temperature of the second supportmember 12, the current that is generated by the temperature differencebetween the first support member 11 and the second support member 12,and that flows from the fourth thermoelectric conversion member 24D tothe third thermoelectric conversion member 23D is drawn to outside usingthe third output section 43 as the positive terminal, and the fourthoutput section 44 as the negative terminal. In this case, becausealternate current flows between the first output section 41 and thesecond output section 42 and between the third output section 43 and thefourth output section 44, the current may be converted into directcurrent using a known half-wave rectifier circuit, followed bysmoothing. The conversion of alternate current into direct current, andthe subsequent smoothing may be performed using the circuit illustratedin FIG. 17A. Alternatively, the conversion of alternate current intodirect current, and the subsequent smoothing may be performed using thecircuit illustrated in FIG. 17B, and the current may be stored in asecondary battery (for example, a thin-film battery). The rectifiercircuit illustrated in FIG. 17A or 17B is also applicable to the otherExamples. Note that the phase of the voltage (“phase-1” for convenience)drawn to outside using the first output section 41 and the second outputsection 42 as the positive and negative terminals, respectively, and thephase of the voltage (“phase-2” for convenience) drawn to outside usingthe third output section 43 and the fourth output section 44 as thepositive and negative terminals, respectively, are out of phase witheach other by about 180°. In other words, phase-1 and phase-2 arereversed phases, or substantially reversed phases.

When the temperature of the first support member 11 is higher than thetemperature of the second support member 12, the current that isgenerated due to the temperature difference between the first supportmember 11 and the second support member 12, and that flows from thefirst thermoelectric conversion member 21D to the second thermoelectricconversion member 22D can be drawn to outside using the second outputsection 42 as the positive terminal, and the first output section 41 asthe negative terminal. When the temperature of the second support member12 is higher than the temperature of the first support member 11, thecurrent that flows from the third thermoelectric conversion member 23Dto the fourth thermoelectric conversion member 24D can be drawn tooutside using the fourth output section 44 as the positive terminal, andthe third output section 43 as the negative terminal. In this case, thealternate current may be converted into direct current using a full-waverectifier circuit, followed by smoothing. The same is applicable toExamples 6 and 7 below.

FIG. 17D is a conceptual view representing an application example of thethermoelectric generator. This application example is a measurementdevice used to obtain biological information such as body temperature,blood pressure, and pulse. The thermoelectric generator supplies powerto the sensor measuring body temperature, blood pressure, pulse, orother information, and to the A/D converter, the transmitter, and thetimer forming the control unit. By the operation of the timer, valuesfrom the sensor are sent to the A/D converter at predetermined timeintervals, and the transmitter sends the data of these values tooutside.

When τ_(SM1)>τ_(SM2), the temperature T_(B) of the second support member12 of the thermoelectric generator placed in a temperature-changingatmosphere (atmospheric temperature T_(amb) at time indicated byellipsoid A in FIG. 7) quickly becomes the atmospheric temperatureT_(amb), or a temperature near T_(amb). On the other hand, becauseτ_(SM1)>τ_(SM2), the temperature T_(A) of the first support member 11varies by lagging behind the temperature change of the second supportmember 12. As a result, a temperature difference ΔT (=T_(B)−T_(A))occurs between the temperature T_(A) (<T_(amb)) of the first supportmember 11 and the temperature T_(B) (=T_(amb)) of the second supportmember 12. As a rule, the relation T₂>T₄>T₃>T₁ is established, where T₁is the temperature in the vicinity of the first surface 21D₁ of thefirst thermoelectric conversion member 21D and the first surface 22D₁ ofthe second thermoelectric conversion member 22D in contact with thefirst support member 11, T₂ is the temperature in the vicinity of thesecond surface 21D₂ of the first thermoelectric conversion member 21Dand the second surface 22D₂ of the second thermoelectric conversionmember 22D in contact with the second support member 12, T₃ is thetemperature in the vicinity of the first surface 23D₁ of the thirdthermoelectric conversion member 23D and the first surface 24D₁ of thefourth thermoelectric conversion member 24D in contact with the firstsupport member 11, and T₄ is the temperature in the vicinity of thesecond surface 23D₂ of the third thermoelectric conversion member 23Dand the second surface 24D₂ of the fourth thermoelectric conversionmember 24D in contact with the second support member 12. Theelectromotive force EMF₁ by a single pair of the first and secondthermoelectric conversion elements, and the electromotive force EMF₂ bya single pair of the third and fourth thermoelectric conversion elementscan be determined as follows.EMF₁ =T ₂ ×SB ₁ −T ₁ ×SB ₂EMF₂ =T ₄ ×SB ₃ −T ₃ ×SB ₄

The same is applicable to Examples 6 and 7 below.

Example 6

Example 6 concerns the thermoelectric generator according to FourthEmbodiment, and the thermoelectric generation method according to FourthEmbodiment B. FIGS. 8A and 8B are schematic partial cross sectional viewof the thermoelectric generator of Example 6. FIG. 9 schematicallyrepresents the temperature (T_(A)) of the first support member, and thetemperature (T_(B)) of the second support member; changes in temperaturedifference between these temperatures (ΔT=T_(B)−T_(A)); changes involtage V₁₋₂ between the first output section and the second outputsection; and changes in voltage V₃₋₄ between the third output sectionand the fourth output section.

In the thermoelectric generator of Example 6, as in the thermoelectricgenerator of Example 5, the first output section 41 is connected to anend portion of the first thermoelectric conversion member 21E on thefirst support member side, and the second output section 42 to an endportion of the second thermoelectric conversion member 22E on the firstsupport member side. However, the third output section 43 is connectedto an end portion of the third thermoelectric conversion member 23E onthe first support member side, and the fourth output section 44 isconnected to an end portion of the fourth thermoelectric conversionmember 24E on the first support member side. In other words, the firstoutput section 41 and the second output section 42, and the third outputsection 43 and the fourth output section 44 are disposed on the samesupport member.

In Example 6, the relations τ_(SM1)≠τ_(SM2), and τ_(TE1)≠τ_(TE2) areestablished, where τ_(SM1) is the thermal response time constant of thefirst support member 11, τ_(SM2) is the thermal response time constantof the second support member 12, τ_(TE1) is the thermal response timeconstant of the first thermoelectric conversion element, and τ_(TE2) isthe thermal response time constant of the second thermoelectricconversion element.

In the thermoelectric generation method of Example 6, the thermoelectricgenerator is placed in a temperature-changing atmosphere. When thetemperature of the second support member 12 is higher than thetemperature of the first support member 11, the current that isgenerated due to the temperature difference between the first supportmember 11 and the second support member 12, and that flows from thesecond thermoelectric conversion member 22E to the first thermoelectricconversion member 21E is drawn to outside using the first output section41 as the positive terminal, and the second output section 42 as thenegative terminal, and that flows from the fourth thermoelectricconversion member 24E to the third thermoelectric conversion member 23Eis drawn to outside using the third output section 43 as the positiveterminal, and the fourth output section 44 as the negative terminal. Inthis case, because alternate current flows between the first outputsection 41 and the second output section 42 and between the third outputsection 43 and the fourth output section 44, the alternate current maybe converted into direct current using, for example, the full-waverectifier circuit illustrated in FIG. 17C, followed by smoothing. Thefull-wave rectifier circuit illustrated in FIG. 17C is also applicableto the other Examples. Note that the phase-1 of the voltage drawn tooutside using the first output section 41 and the second output section42 as the positive and negative terminals, and the phase-2 of thevoltage drawn to outside using the third output section 43 and thefourth output section 44 as the positive and negative terminals are outof phase with each other by greater than 0° and less than 180°.

Example 7

Example 7 is a variation of Example 6. FIGS. 10A and 10B are schematicpartial cross sectional views of the thermoelectric generator of Example7. FIG. 11 schematically represents the temperature (T_(A)) of the firstsupport member, and the temperature (T_(B)) of the second supportmember; changes in temperature difference between these temperatures(ΔT=T_(B)−T_(A)); changes in voltage V₁₋₂ between the first outputsection and the second output section; and changes in voltage V₃₋₄between the third output section and the fourth output section.

In the thermoelectric generator of Example 6, the first thermoelectricconversion member 21E, the second thermoelectric conversion member 22E,the third thermoelectric conversion member 23E, and the fourththermoelectric conversion member 24E have the shape of truncatedquadrangular pyramids. In contrast, in the thermoelectric generator ofExample 7, the first thermoelectric conversion member 21F, the secondthermoelectric conversion member 22F, the third thermoelectricconversion member 23F, and the fourth thermoelectric conversion member24F have the shape of quadrangular columns. Further, the relationsVL₁≠VL₃, VL₂≠VL₄, VL₁≠VL₂, and VL₃≠VL₄ are established, where VL₁ is thevolume of the first thermoelectric conversion member 21, VL₂ the volumeof the second thermoelectric conversion member 22, VL₃ the volume of thethird thermoelectric conversion member 23, and VL₄ the volume of thefourth thermoelectric conversion member 24. The thermoelectric generatorand the thermoelectric generation method of Example 7 are the same asthe thermoelectric generator and the thermoelectric generation method ofExample 6 except for these points, and thus will not be described indetail.

Example 8

Example 8 concerns the thermoelectric generation method according toFifth Embodiment A. FIGS. 12A and 12B are schematic partial crosssectional views of a thermoelectric generator suitable for use in thethermoelectric generation method of Example 8. FIG. 13 schematicallyrepresents the temperature (T_(A)) of the first support member, and thetemperature (T_(B)) of the second support member; changes in temperaturedifference between these temperatures (ΔT=T_(B)−T_(A)); changes involtage V₁₋₂ between the first output section and the second outputsection; and changes in voltage V₃₋₄ between the third output sectionand the fourth output section.

The thermoelectric generator of Example 8 or Examples 9 and 10 belowincludes:

(A) a first support member 11;

(B) a second support member 12 disposed opposite the first supportmember 11;

(C) a first thermoelectric conversion element 121G, 121H, or 121Jdisposed between the first support member 11 and the second supportmember 12;

(D) a second thermoelectric conversion element 122G, 122H, or 122Jdisposed between the first support member 11 and the second supportmember 12;

(E) a third thermoelectric conversion element 123G, 123H, or 123Jdisposed between the first support member 11 and the second supportmember 12;

(F) a fourth thermoelectric conversion element 124G, 124H, or 124Jdisposed between the first support member 11 and the second supportmember 12; and

(G) a first output section 141, a second output section 142, a thirdoutput section 143, and a fourth output section 144.

The first thermoelectric conversion element 121G, 121H, or 121J includesa first thermoelectric conversion member A-121G_(A), 121H_(A), or121J_(A) in contact with the second support member 12, and a firstthermoelectric conversion member B-121G_(B), 121H_(B), or 121J_(B) incontact with the first support member 11. The first thermoelectricconversion member A-121G_(A), 121H_(A), or 121J_(A) and the firstthermoelectric conversion member B-121G_(B), 121H_(B), or 121J_(B) aredisposed in contact with (specifically, laminated with) each other.

The second thermoelectric conversion element 122G, 122H, or 122Jincludes a second thermoelectric conversion member A-122G_(A), 122H_(A),or 122J_(A) in contact with the first support member 11, and a secondthermoelectric conversion member B-122G_(B), 122H_(B), or 122J_(B) incontact with the second support member 12. The second thermoelectricconversion member A-122G_(A), 122H_(A), or 122J_(A) and the secondthermoelectric conversion member B-122G_(B), 122H_(B), or 122J_(B) aredisposed in contact with (specifically, laminated with) each other.

The third thermoelectric conversion element 123G, 123H, or 123J includesa third thermoelectric conversion member A-123G_(A), 123H_(A), or123J_(A) in contact with the second support member 12, and a thirdthermoelectric conversion member B-123G_(B), 123H_(B), or 123J_(B) incontact with the first support member 11. The third thermoelectricconversion member A-123G_(A), 123H_(A), or 123J_(A) and the thirdthermoelectric conversion member B-123G_(B), 123H_(B), or 123J_(B) aredisposed in contact with (specifically, laminated with) each other.

The fourth thermoelectric conversion element 124G, 124H, or 124Jincludes a fourth thermoelectric conversion member A-124G_(A), 124H_(A),or 124J_(A) in contact with the first support member 11, and a fourththermoelectric conversion member B-124G_(B), 124H_(B), 124J_(B) incontact with the second support member 12. The fourth thermoelectricconversion member A-124G_(A), 124H_(A), or 124J_(A) and the fourththermoelectric conversion member B-124G_(B), 124H_(B), or 124J_(B) aredisposed in contact with (specifically, laminated with) each other.

The first thermoelectric conversion element 121G, 121H, or 121J and thesecond thermoelectric conversion element 122G, 122H, or 122J areelectrically connected to each other in series. The third thermoelectricconversion element 123G, 123H, or 123J and the fourth thermoelectricconversion element 124G, 124H, or 124J are electrically connected toeach other in series. The first output section 141 is connected to thefirst thermoelectric conversion element 121G, 121H, or 121J. The secondoutput section 142 is connected to the second thermoelectric conversionelement 122G, 122H, or 122J. The third output section 143 is connectedto the third thermoelectric conversion element 123G, 123H, or 123J. Thefourth output section 144 is connected to the fourth thermoelectricconversion element 124G, 124H, or 124J. In other words, the first outputsection 141 and the second output section 142, and the third outputsection 143 and the fourth output section 144 are disposed on differentsupport members.

Specifically, in Example 8, the first output section 141 is connected toan end portion of the first thermoelectric conversion member B-121G_(B),the second output section 142 to an end portion of the secondthermoelectric conversion member A-122G_(A), the third output section143 to an end portion of the third thermoelectric conversion memberA-123G_(A), and the fourth output section 144 to an end portion of thefourth thermoelectric conversion member B-124G_(B). More specifically,the first thermoelectric conversion member A-121G_(A) and the secondthermoelectric conversion member B-122G_(B) are electrically connectedto each other via a wire 31B provided on the second support member 12,the second thermoelectric conversion member A-122G_(A) and the firstthermoelectric conversion member B-121G_(B) are electrically connectedto each other via a wire 31A provided on the first support member 11,the third thermoelectric conversion member A-123G_(A) and the fourththermoelectric conversion member B-124G_(B) are electrically connectedto each other via a wire 32B provided on the second support member 12,and the fourth thermoelectric conversion member A-124G_(A) and the thirdthermoelectric conversion member B-123G_(B) are electrically connectedto each other via a wire 32A provided on the first support member 11.

Further, in Example 8, the relation τ_(SM1)≠τ_(SM2) is established,where τ_(SM1) is the thermal response time constant of the first supportmember 11, and τ_(SM2) is the thermal response time constant of thesecond support member 12. The first thermoelectric conversion element121G, the second thermoelectric conversion element 122G, the thirdthermoelectric conversion element 123G, and the fourth thermoelectricconversion element 124G are columnar in shape, specifically,quadrangular columns.

In the thermoelectric generation method of Example 8, the thermoelectricgenerator is placed in a temperature-changing atmosphere. When thetemperature of the second support member 12 is higher than thetemperature of the first support member 11, the current that isgenerated due to the temperature difference between the first supportmember 11 and the second support member 12, and that flows from thesecond thermoelectric conversion element 122G to the firstthermoelectric conversion element 121G is drawn to outside using thefirst output section 141 as the positive terminal, and the second outputsection 142 as the negative terminal. On the other hand, when thetemperature of the first support member 11 is higher than thetemperature of the second support member 12, the current that flows dueto the temperature difference between the first support member 11 andthe second support member 12, and that flows from the thirdthermoelectric conversion element 123G to the fourth thermoelectricconversion element 124G is drawn to outside using the fourth outputsection 144 as the positive terminal, and the third output section 143as the negative terminal. In this case, because alternate current flowsbetween the first output section 141 and the second output section 142and between the third output section 143 and the fourth output section144, the alternate current may be converted into direct current using aknown half-wave rectifier circuit, followed by smoothing. Note that thephase-1 of the voltage drawn to outside using the first output section141 and the second output section 142 as the positive and negativeterminals, and the phase-2 of the voltage drawn to outside using thethird output section 143 and the fourth output section 144 as thenegative and positive terminals are out of phase with each other byabout 180°. In other words, phase-1 and phase-2 are reversed phases, orsubstantially reversed phases.

When the temperature of the first support member 11 is higher than thetemperature of the second support member 12, the current that isgenerated due to the temperature difference between the first supportmember 11 and the second support member 12, and that flows from thefirst thermoelectric conversion element 121G to the secondthermoelectric conversion element 122G can be drawn to outside using thesecond output section 142 as the positive terminal, and the first outputsection 141 as the negative terminal. When the temperature of the secondsupport member 12 is higher than the temperature of the first supportmember 11, the current that flows from the fourth thermoelectricconversion element 124G to the third thermoelectric conversion element123G can be drawn to outside using the third output section 143 as thepositive terminal, and the fourth output section 144 as the negativeterminal. In this case, the alternate current may be converted intodirect current using a known full-wave rectifier circuit, followed bysmoothing. The same is applicable to Examples 9 and 10 below.

When τ_(SM1)>τ_(SM2), the temperature T_(B) of the second support member12 of the thermoelectric generator placed in a temperature-changingatmosphere (atmospheric temperature T_(amb) at time indicated byellipsoid A in FIG. 13) quickly becomes the atmospheric temperatureT_(amb), or a temperature near T_(amb). On the other hand, becauseτ_(SM1)>τ_(SM2), the temperature T_(A) of the first support member 11varies by lagging behind the temperature change of the second supportmember 12. As a result, a temperature difference ΔT (=T_(B)−T_(A))occurs between the temperature T_(A) (<T_(amb)) of the first supportmember 11 and the temperature T_(B) (=T_(amb)) of the second supportmember 12. The relations T₂>T₁, and T₄>T₃ are established, where T₂ isthe temperature in the vicinity of the second surface 121G₂ of the firstthermoelectric conversion member A-121G_(A) and the second surface 122G₂of the second thermoelectric conversion member B-122G_(B) in contactwith the second support member 12, T₁ is the temperature in the vicinityof the first surface 121G₁ of the first thermoelectric conversion memberB-121G_(B) and the first surface 122G₁ of the second thermoelectricconversion member A-122G_(A) in contact with the first support member11, T₄ is the temperature in the vicinity of the second surface 123G₂ ofthe third thermoelectric conversion member A-123G_(A) and the secondsurface 124G₂ of the fourth thermoelectric conversion member B-124G_(B)in contact with the second support member 12, and T₃ is the temperaturein the vicinity of the first surface 123G₁ of the third thermoelectricconversion member B-123G_(B) and the first surface 124G₁ of the fourththermoelectric conversion member A-124G_(A) in contact with the firstsupport member 11. The electromotive force EMF₁ by a single pair of thefirst thermoelectric conversion element and the second thermoelectricconversion element, and the electromotive force EMF₂ by a single pair ofthe third thermoelectric conversion element and the fourththermoelectric conversion element can be determined as follows.EMF₁ =T ₂ ×SB ₁ −T ₁ ×SB ₂EMF₂ =T ₄ ×SB ₃ −T ₃ ×SB ₄

Example 9

Example 9 concerns the thermoelectric generator according to FifthEmbodiment, and the thermoelectric generation method according to FifthEmbodiment B. FIGS. 14A and 14B are schematic partial cross sectionalviews of the thermoelectric generator of Example 9. FIG. 15schematically represents the temperature (T_(A)) of the first supportmember, and the temperature (T_(B)) of the second support member;changes in temperature difference between these temperatures(ΔT=T_(B)−T_(A)); changes in voltage V₁₋₂ between the first outputsection and the second output section; and changes in voltage V₃₋₄between the third output section and the fourth output section.

In Example 9 or Example 10 below, the first output section 141 isconnected to an end portion of the first thermoelectric conversionmember B-121H_(B) or 121J_(B), the second output section 142 isconnected to an end portion of the second thermoelectric conversionmember A-122H_(A) or 122J_(A), the third output section 143 is connectedto an end portion of the third thermoelectric conversion memberB-123H_(B) or 123J_(B), and the fourth output section 144 is connectedto an end portion of the fourth thermoelectric conversion memberA-124H_(A) or 124J_(A). In other words, the first output section 141 andthe second output section 142, and the third output section 143 and thefourth output section 144 are disposed on the same support member. Thefirst thermoelectric conversion member A-121H_(A) or 121J_(A) and thesecond thermoelectric conversion member B-122H_(B) or 122J_(B) areelectrically connected to each other via a wire 31B provided on thesecond support member 12. The first thermoelectric conversion memberB-121H_(B) or 121J_(B) and the second thermoelectric conversion memberA-122H_(A) or 122J_(A) are electrically connected to each other via awire 31A provided on the first support member 11. The thirdthermoelectric conversion member A-123H_(A) or 123J_(A) and the fourththermoelectric conversion member B-124H_(B) or 124J_(B) are electricallyconnected to each other via a wire 32B provided on the second supportmember 12. The third thermoelectric conversion member B-123H_(B) or123J_(B) and the fourth thermoelectric conversion member A-124H_(A) or124J_(A) are electrically connected to each other via a wire 32Aprovided on the first support member 11.

Further, when τ_(SM1) is the thermal response time constant of the firstsupport member 11, and τ_(SM2) is the thermal response time constant ofthe second support member 12, the relations τ_(TE1)≠τ_(TE3), andτ_(TE2)≠τ_(TE4), are established, where τ_(TE1) is the thermal responsetime constant of the first thermoelectric conversion element 121H or121J, τ_(TE2) is the thermal response time constant of the secondthermoelectric conversion element 122H or 122J, τ_(TE3) is the thermalresponse time constant of the third thermoelectric conversion element123H or 123J, and τ_(TE4) is the thermal response time constant of thefourth thermoelectric conversion element 124H or 124J. Further, inExample 9, VL₁=VL₂≠VL₃=VL₄ (specifically, VL₁=VL₂<VL₃=VL₄ in Example 9),where VL₁ is the volume of the first thermoelectric conversion element121H, VL₂ the volume of the second thermoelectric conversion element122H, VL₃ the volume of the third thermoelectric conversion element123H, and VL₄ the volume of the fourth thermoelectric conversion element124H. The first thermoelectric conversion element 121H, the secondthermoelectric conversion element 122H, the third thermoelectricconversion element 123H, and the fourth thermoelectric conversionelement 124H are columnar in shape, specifically, quadrangular columns.

In the thermoelectric generation method of Example 9, the thermoelectricgenerator is placed in a temperature-changing atmosphere. When thetemperature of the second support member 12 is higher than thetemperature of the first support member 11, the current that isgenerated due to the temperature difference between the first supportmember 11 and the second support member 12, and that flows from thesecond thermoelectric conversion element 122H to the firstthermoelectric conversion element 121H is drawn to outside using thefirst output section 141 as the positive terminal, and the second outputsection 142 as the negative terminal, and that flows from the fourththermoelectric conversion element 124H to the third thermoelectricconversion element 123H is drawn to outside using the third outputsection 143 as the positive terminal, and the fourth output section 144as the negative terminal. In this case, because alternate current flowsbetween the first output section 141 and the second output section 142and between the third output section 143 and the fourth output section144, the current may be converted into direct current using a knownhalf-wave rectifier circuit, followed by smoothing. Note that thephase-1 of the voltage drawn to outside using the first output section141 and the second output section 142 as the positive and negativeterminals, respectively, and the phase-2 of the voltage drawn to outsideusing the third output section 143 and the fourth output section 144 asthe positive and negative terminals, respectively, are out of phase witheach other by greater than 0° and less than 180°.

When τ_(SM1)>τ_(SM2), the temperature T_(B) of the second support member12 of the thermoelectric generator placed in a temperature-changingatmosphere (atmospheric temperature T_(amb) at time indicated byellipsoid A in FIG. 15) quickly becomes the atmospheric temperatureT_(amb), or a temperature near T_(amb). On the other hand, becauseτ_(SM1)>τ_(SM2), the temperature T_(A) of the first support member 11varies by lagging behind the temperature change of the second supportmember 12. As a result, a temperature difference ΔT (=T_(B)−T_(A))occurs between the temperature T_(A) (<T_(amb)) of the first supportmember 11 and the temperature T_(B) (=T_(amb)) of the second supportmember 12. The relations T₂>T₁, and T₄>T₃ are established, where T₂ isthe temperature in the vicinity of the second surface 121H₂ of the firstthermoelectric conversion member A-121H_(A) and the second surface 122H₂of the second thermoelectric conversion member B-122H_(B) in contactwith the second support member 12, T₁ is the temperature in the vicinityof the first surface 121H₁ of the first thermoelectric conversion memberA-121H_(A) and the first surface 122H₁ of the second thermoelectricconversion member B-122H_(B) in contact with the first support member11, T₄ is the temperature in the vicinity of the second surface 123H₂ ofthe third thermoelectric conversion member A-123H_(A) and the secondsurface 124H₂ of the fourth thermoelectric conversion member B-124H_(B)in contact with the second support member 12, and T₃ is the temperaturein the vicinity of the first surface 123H₁ of the third thermoelectricconversion member A-123H_(A) and the first surface 124H₁ of the fourththermoelectric conversion member B-124H_(B) in contact with the firstsupport member 11. The electromotive force EMF₁ by a single pair of thefirst thermoelectric conversion element and the second thermoelectricconversion element, and the electromotive force EMF₂ by a single pair ofthe third thermoelectric conversion element and the fourththermoelectric conversion element can be determined as follows.EMF₁ =T ₂ ×SB ₁ −T ₁ ×SB ₂EMF₂ =T ₄ ×SB ₃ −T ₃ ×SB ₄

Example 10

Example 10 is a variation of Example 9. FIGS. 16A and 16B are schematicpartial cross sectional views of the thermoelectric generator of Example10.

In the thermoelectric generator of Example 9, the first thermoelectricconversion element 121H, the second thermoelectric conversion element122H, the third thermoelectric conversion element 123H, and the fourththermoelectric conversion element 124H have the shape of quadrangularcolumns. In contrast, in the thermoelectric generator of Example 10, thefirst thermoelectric conversion element 121J, the second thermoelectricconversion element 122J, the third thermoelectric conversion element123J, and the fourth thermoelectric conversion element 124J have theshape of truncated quadrangular pyramids. Specifically, the relationsS₁₂≠S₃₂, and S₂₁≠S₄₁, and the relations S₁₂≠S₂₁, and S₃₁≠S₄₂ areestablished, where S₁₂ is the area of the first thermoelectricconversion member A-121J_(A) in a portion (second surface 121J₂) incontact with the second support member 12, S₂₂ is the area of the secondthermoelectric conversion member B-122J_(B) in a portion (second surface122J₂) in contact with the second support member 12, S₁₁ is the area ofthe first thermoelectric conversion member B-121J_(B) in a portion(first surface 121J₁₁) in contact with the first support member 11, S₂₁is the area of the second thermoelectric conversion member A-122J_(A) ina portion (first surface 122J₁) in contact with the first support member11, S₃₂ is the area of the third thermoelectric conversion memberA-123J_(A) in a portion (second surface 123J₂) in contact with thesecond support member 12, S₄₂ is the area of the fourth thermoelectricconversion member B-124J_(B) in a portion (second surface 124J₂) incontact with the second support member 12, S₃₁ is the area of the thirdthermoelectric conversion member B-123J_(B) in a portion (first surface123J₁) in contact with the first support member 11, and S₄₁ is the areaof the fourth thermoelectric conversion member A-124J_(A) in a portion(first surface 124J₁) in contact with the first support member 11. Thethermoelectric generator, and the thermoelectric generation method ofExample 10 can be configured in the same way as the thermoelectricgenerator, and the thermoelectric generation method of Example 9 exceptfor these points, and thus will not be described in detail.

Example 11

In Example 11, power was supplied to a digital humidity sensor module(Mother Tool Co., LTD.: Model MT-160) via a voltage multiplier circuitand a boost circuit (Seiko Instruments Inc.: boost DC-DCconverter-starting ultra-low voltage operation charge pump IC S-882Z18),using a thermoelectric generator of substantially the same structure asthat described in Example 2. The temperature-changing atmosphere of thethermoelectric generator was as follows:

ΔT_(amb): about 4.5° C.

Temperature change cycle TM: 15 min

Air wind speed: about 1 msec

The thermoelectric generator placed in this atmosphere produced amaximum voltage of 750 millivolts, and an average power of 44.2microwatts/200 cm² was obtained during 15 hours of thermoelectricgeneration. It was therefore possible to supply the required voltage andpower of 1 volt and 4.5 microwatts specified for the operation of thedigital humidity sensor module.

Example 12

Example 12 concerns the electrical signal detecting method according toFirst Embodiment, and the electrical signal detecting device accordingto an embodiment. The electrical signal detecting method of Example 12is an electrical signal detecting method that uses an electrical signaldetecting device produced by using the thermoelectric generatoraccording to First Embodiment described in Example 1. In the electricalsignal detecting method of Example 12, the thermoelectric generator isalso placed in a temperature-changing atmosphere. Essentially as inExample 1, when the temperature of the second support member 12 ishigher than the temperature of the first support member 11, the currentthat is generated due to the temperature difference between the firstsupport member 11 and the second support member 12, and that flows fromthe second thermoelectric conversion member 22A or 22B to the firstthermoelectric conversion member 21A or 21B is drawn to outside as anelectrical signal, using the first output section 41 as the positiveterminal (plus terminal), and the second output section 42 as thenegative terminal (minus terminal). In contrast to Example 1 in whichthe current that flows from the second thermoelectric conversion member22A or 22B to the first thermoelectric conversion member 21A or 21B isused as energy source, in Example 12, the current that flows from thesecond thermoelectric conversion member 22A or 22B to the firstthermoelectric conversion member 21A or 21B is used as electricalsignal, specifically, an electrical signal that conveys information.Different kinds of electrical signals are obtained from this electricalsignal.

For example, there is a correlation between the biological informationhuman heart rate and body temperature. The agreed increment of heartrate per 1° C. of body temperature is 8 beats/° C. to 10 beats/° C. Bodytemperature also fluctuates according to such factors as stress,consciousness level, and clinical conditions. It is therefore possibleto monitor biological information such as pulse, stress level,consciousness level, and clinical conditions by sensing temperatureinformation (absolute temperature, relative temperature, fluctuationcycle) through electrical signal detection. Further, because theelectrical signal detecting device used is produced from thethermoelectric generator, the monitoring may involve thermoelectricgeneration. Specifically, the current that flows from the secondthermoelectric conversion member 22A or 22B to the first thermoelectricconversion member 21A or 21B can be used not only as an electricalsignal, specifically an information-conveying electrical signal, but asan energy source. The thermoelectric energy may be temporarily stored ina capacitor or a secondary battery, and then brought to other uses (forexample, the energy source of the measurement device represented in FIG.17D).

In the electrical signal detecting method of Example 12, the generatedpower is due to the temperature difference between ambient temperatureand subject temperature (for example, body temperature), when, forexample, one of the temperature contacts is the measurement face, andwhen the other temperature contact is the atmosphere. In this case, theelectrical signal (output signal) becomes the composite wave ofelectromotive forces due to not only the ambient temperature fluctuationcycle and fluctuation range, but the subject temperature (for example,body temperature) fluctuation cycle and fluctuation range. The type ofthe detected electrical signal according to the temperature fluctuationcycle becomes different for, for example, stress level, and thefluctuation of body temperature due to movement. Thus, the electricalsignal is the composite signal of these and other electrical signals.Thus, the electrical signal (for convenience, “pre-process electricalsignal”) is obtained based on the current that flows from the secondthermoelectric conversion member 22A or 22B to the first thermoelectricconversion member 21A or 21B. The electrical signal (pre-processelectrical signal) can then be subjected to post-processes, for example,such as frequency analysis, to obtain different kinds of electricalsignals (for convenience, “post-process electrical signals”).

For example, the post-process uses a hidden Markov model. Specifically,a temperature signal model of characteristic patterns contained in apredetermined cycle or in a certain signal intensity is acquired, forexample, as a signal unit that independently occurs in each constitutingelement/various factors, or as a signal that has a correlation with aplurality of constituting elements/a plurality of factors at the sametime, and that originates in a specific factor. Here, the periodicityobtained specific to each of the thermoelectric conversion elements ofdifferent thermal time constants in the image of a tuning fork isutilized. Specifically, in the presence of cyclic temperaturefluctuations of a certain temperature fluctuation range, a signal from athermoelectric conversion element that produces the output with thesmallest loss from among the thermoelectric conversion elements ofdifferent thermal time constants over this temperature fluctuation rangeis extracted. Frequency decomposition is made possible only by thisprocedure, without the need for complex arithmetic processes. Basically,the same process can be used also for the composite wave of differentsignals. The enablement of such processes is advantageous, for example,in reducing the number of operations for the input waveforms ofconsiderably different sampling cycles of sufficient accuracy in, forexample, FFT (Fast Fourier/Cosine/Sine Transform) spectral analysis.This is because each thermoelectric conversion element has its ownfrequency of specialty, and thus enables a sufficient sampling cycle tobe set beforehand for the spectral analysis. When the thermoelectricconversion elements all have the same thermal time constant, FFTspectral analysis will be necessary, or the spectral analysis may beused alone even when thermal time constants are different. In the modelextraction, a characteristic state is extracted by a pre-process, whichmay be, for example, PCA (Principal Components Analysis) or ICA(Independent Component Analysis). A probability density functionconcerning the extracted state is then determined, and a statetransition model is created. The state transition model may be createdfor each of the thermoelectric conversion elements of different thermaltime constants. For the pre-process electrical signal, a statetransition path that yields the best probability score for the outputseries is selected using, for example, a Viterbi algorithm, and thepost-process electrical signal can be obtained upon optimum pathtracking. The optimum path tracking may be performed for each of thethermoelectric conversion elements of different thermal time constants.The same post-process may be performed in Examples 13 to 18 below.

Specifically, for example, the extraction of a body temperaturefluctuation cycle from an electrical signal that contains the ambienttemperature fluctuation cycle and the body temperature fluctuation cycleis preceded by feature extraction for the ambient fluctuation model andthe body temperature fluctuation model as state transition models basedon PCA or ICA. Here, temperature data for, for example, ambienttemperature fluctuation can be acquired based on common convective heattransfer/radiative heat transfer. In contrast, temperature data for thebody temperature can be acquired based on heat conduction or radiation.Because the skin has larger heat capacity than air, skin temperaturefluctuations lag behind the ambient temperature fluctuation. The ambienttemperature fluctuation has a relatively short cycle, and the signaleasily fluctuates. In the case of radiative heat transfer, thethermoelectric conversion element involves different emissivities,different configuration factors, and different absorption spectra forthe surroundings and the body. A plurality of state transition modelsresults from these different data acquisition methods, the heat capacityof the subject, emissivity and other material properties, anddifferences in constant such as the configuration factor. By determiningthe probability density distribution according to the situation of eachstate transition model acquired beforehand, state determination can bemade by optimum path tracking in actual monitoring. The stress levelextracted from the electrical signal that contains the ambienttemperature fluctuation cycle and stress level is determined from acombination of a plurality of signals, specifically, skin surfacetemperature, sweat level, heart rate, and pulse. The signals for theheart rate and pulse can be obtained from body temperature measurement.Considering that the heat-transfer coefficient on the skin surfacevaries by sweating, the signal for the sweat level can be obtained fromtemperature measurement. The signals originate from different sources,and thus their cycles do not match, provided that the sampling cyclesare sufficient. This enables signal extraction by frequencydecomposition that uses the characteristic frequency of thethermoelectric conversion element, or by other techniques such as FFTand spectral analysis. Feature extraction is then performed based on PCAor ICA for each of the signals, and upon acquisition of state transitionmodels, a probability density distribution is determined according tothe situation of each model. State determination is made by optimum pathtracking in actual monitoring. The same is applicable to Examples 13 to18 below.

The electrical signal detecting device of Example 12 operates based onthese principles. Specifically, the electrical signal detecting deviceof Example 12 includes at least two of the thermoelectric generatorsaccording to First to Fifth Embodiments described in Examples 1 to 10,and the current obtained from each thermoelectric generator is obtainedas an electrical signal. By the provision of at least two of thethermoelectric generators according to First to Fifth Embodimentsdescribed in Examples 1 to 10, detection of information (electricalsignal) not possible with an electrical signal detecting device providedwith only one thermoelectric generator, or detection of more than oneinformation item (electrical signal) is enabled. Specifically, forexample, by combining the thermoelectric generators described inExamples 1 and 4, an electrical signal detecting device can be realizedthat includes a thermoelectric generator suited for measuring bloodpressure, and a thermoelectric generator suited for measuring heartrate. The electrical signal detecting device also serves as athermoelectric generator. As required, the resulting electrical signalmay be passed through a bandpass filter, a lowpass filter, or a highpassfilter. The electrical signal detecting device of Example 12 is alsoapplicable to Examples 13 to 18 below.

As described above, the thermal response time constant τ is determinedby the density ρ, specific heat c, and heat-transfer coefficient h ofthe materials forming the support member, the thermoelectric conversionelement, and the thermoelectric conversion member, and the volume VL andarea S of the support member, the thermoelectric conversion element, andthe thermoelectric conversion member. Thus, desired information(electrical signal) can be obtained by appropriately selecting thesevariables. In this way, an electrical signal detecting device can beobtained that includes thermoelectric generators of different thermalresponse time constants τ. Because of the difference in thermal responsewith respect to temperature changes, a plurality of electrical signalscan be obtained from the electrical signal detecting device, and thusmore than one information item can be obtained from the singleelectrical signal detecting device. Typical heart rate of humans isabout 50 to 90 for adults, and about 50 to 100 for children. Forexample, thermal response time constant τ may be 0.1 to 5, preferably 1to 3. For blood pressure fluctuation, thermal response time constant τmay be, for example, 10 to 60 for signals in an active state, and may be3 to 6 for signals in a breathing state.

Example 13

Example 13 is the electrical signal detecting method according to SecondEmbodiment. The electrical signal detecting method of Example 13 is anelectrical signal detecting method that uses the thermoelectricgenerator according to Second Embodiment described in Example 2. InExample 13, the thermoelectric generator is placed in atemperature-changing atmosphere, as in Example 3. Further, essentiallyas in Example 3, when the temperature of the second support member 12 ishigher than the temperature of the first support member 11, the currentthat is generated due to the temperature difference between the firstsupport member 11 and the second support member 12, and that flows fromthe second thermoelectric conversion member 22A or 22B to the firstthermoelectric conversion member 21A or 21B is drawn to outside aselectrical signal, using the first output section 41 as the positiveterminal (plus terminal), and the second output section 42 as thenegative terminal (minus terminal). Further, as in Example 12, differentkinds of electrical signals (post-process electrical signals) areobtained from the electrical signal (pre-process electrical signal).

Example 14

Example 14 is the electrical signal detecting method according to ThirdEmbodiment. The electrical signal detecting method of Example 14 is anelectrical signal detecting method that uses the thermoelectricgenerator according to Third Embodiment described in Examples 3 and 4.In Example 14, as in Examples 3 and 4, the thermoelectric generator isplaced in a temperature-changing atmosphere. Further, essentially as inExamples 3 and 4, when the temperature of the second support member 12or 212 is higher than the temperature of the first support member 11 or211, the current that is generated due to the temperature differencebetween the first support member 11 or 211 and the second support member12 or 212, and that flows from the second thermoelectric conversionelement 122C or 222C to the first thermoelectric conversion element 121Cor 221C is drawn to outside as an electrical signal, using the firstoutput section 141 or 241 as the positive terminal, and the secondoutput section 142 or 242 as the negative terminal. Further, as inExample 12, different kinds of electrical signals (post-processelectrical signals) are obtained from the electrical signal (pre-processelectrical signal).

Example 15

Example 15 is the electrical signal detecting method according to FourthEmbodiment A. The electrical signal detecting method of Example 15 is anelectrical signal detecting method that uses the thermoelectricgenerator according to Fourth Embodiment described in Example 5. InExample 15, as in Example 5, the thermoelectric generator is placed in atemperature-changing atmosphere. Further, essentially as in Example 5,when the temperature of the second support member 12 is higher than thetemperature of the first support member 11, the current that isgenerated due to the temperature difference between the first supportmember 11 and the second support member 12, and that flows from thesecond thermoelectric conversion member 22D to the first thermoelectricconversion member 21D is drawn to outside as an electrical signal, usingthe first output section 41 as the positive terminal, and the secondoutput section 42 as the negative terminal. On the other hand, when thetemperature of the first support member 11 is higher than thetemperature of the second support member 12, the current that isgenerated due to the temperature difference between the first supportmember 11 and the second support member 12, and that flows from thefourth thermoelectric conversion member 24D to the third thermoelectricconversion member 23D is drawn to outside as an electrical signal, usingthe third output section 43 as the positive terminal, and the fourthoutput section 44 as the negative terminal. Further, as in Example 12,different kinds of electrical signals (post-process electrical signals)are obtained from the electrical signal (pre-process electrical signal).

Example 16

Example 16 is the electrical signal detecting method according to FourthEmbodiment B. The electrical signal detecting method of Example 16 is anelectrical signal detecting method that uses the thermoelectricgenerator according to Fourth Embodiment described in Examples 6 and 7.In Example 16, as in Examples 6 and 7, the thermoelectric generator isplaced in a temperature-changing atmosphere. Further, essentially as inExamples 6 and 7, when the temperature of the second support member 12is higher than the temperature of the first support member 11, thecurrent that is generated due to the temperature difference between thefirst support member 11 and the second support member 12, and that flowsfrom the second thermoelectric conversion members 22E and 22F to thefirst thermoelectric conversion members 21E and 21F is drawn to outsideas an electrical signal, using the first output section 41 as thepositive terminal, and the second output section 42 as the negativeterminal, and that flows from the fourth thermoelectric conversionmembers 24E and 24F to the third thermoelectric conversion members 23Eand 23F is drawn to outside as an electrical signal, using the thirdoutput section 43 as the positive terminal, and the fourth outputsection 44 as the negative terminal. Further, as in Example 12,different kinds of electrical signals (post-process electrical signals)are obtained from the electrical signal (pre-process electrical signal).

Example 17

Example 17 is the electrical signal detecting method according to FifthEmbodiment A. The electrical signal detecting method of Example 17 is anelectrical signal detecting method that uses the thermoelectricgenerator according to Fifth Embodiment described in Example 8. InExample 17, as in Example 8, the thermoelectric generator is placed in atemperature-changing atmosphere. Further, essentially as in Example 8,when the temperature of the second support member 12 is higher than thetemperature of the first support member 11, the current that isgenerated due to the temperature difference between the first supportmember 11 and the second support member 12, and that flows from thesecond thermoelectric conversion element 122G to the firstthermoelectric conversion element 121G is drawn to outside as anelectrical signal, using the first output section 141 as the positiveterminal, and the second output section 142 as the negative terminal. Onthe other hand, when the temperature of the first support member 11 ishigher than the temperature of the second support member 12, the currentthat is generated due to the temperature difference between the firstsupport member 11 and the second support member 12, and the flows fromthe third thermoelectric conversion element 123G to the fourththermoelectric conversion element 124G is drawn to outside as anelectrical signal, using the fourth output section 144 as the positiveterminal, and the third output section 143 as the negative terminal.Further, as in Example 12, different kinds of electrical signals(post-process electrical signals) are obtained from the electricalsignal (pre-process electrical signal).

Example 18

Example 18 is the electrical signal detecting method according to FifthEmbodiment B. The electrical signal detecting method of Example 18 is anelectrical signal detecting method that uses the thermoelectricgenerator according to Fifth Embodiment described in Examples 9 and 10.In Example 18, as in Examples 9 and 10, the thermoelectric generator isplaced in a temperature-changing atmosphere. Further, essentially as inExamples 9 and 10, when the temperature of the second support member 12is higher than the temperature of the first support member 11, thecurrent that is generated due to the temperature difference between thefirst support member 11 and the second support member 12, and that flowsfrom the second thermoelectric conversion element 122H or 122J to thefirst thermoelectric conversion element 121H or 121J is drawn to outsideas an electrical signal, using the first output section 141 as thepositive terminal, and the second output section 142 as the negativeterminal, and that flows from the fourth thermoelectric conversionelement 124H or 124J to the third thermoelectric conversion element 123Hor 123J is drawn to outside as an electrical signal, using the thirdoutput section 143 as the positive terminal, and the fourth outputsection 144 as the negative terminal. Further, as in Example 12,different kinds of electrical signals (post-process electrical signals)are obtained from the electrical signal (pre-process electrical signal).

The structures and configurations of the thermoelectric generatorsdescribed in the Examples, and variables such as the material and sizepresented above are merely examples, and may be appropriately changed.For example, instead of using the p-type conductivity elementsbismuth.tellurium.antimony for the first thermoelectric conversionmember, the third thermoelectric conversion member, the firstthermoelectric conversion member A, the second thermoelectric conversionmember A, the third thermoelectric conversion member A, and the fourththermoelectric conversion member A, materials such as Mg₂Si, SrTiO₃,MnSi₂, Si—Ge-based material, β-FeSi₂, PbTe-based material, ZnSb-basedmaterial, CoSb-based material, Si-based material, clathrate compounds,NaCo₂O₄, Ca₃Co₄O₉, and Chromel alloys may be used. Further, instead ofusing the n-type conductivity elements bismuth.tellurium for the secondthermoelectric conversion member, the fourth thermoelectric conversionmember, the first thermoelectric conversion member B, the secondthermoelectric conversion member B, the third thermoelectric conversionmember B, and the fourth thermoelectric conversion member B, materialssuch as Mg₂Si, SrTiO₃, MnSi₂, Si—Ge-based material, β-FeSi₂, PbTe-basedmaterial, ZnSb-based material, CoSb-based material, Si-based material,clathrate compounds, constantan, and Alumel alloys may be used. Further,the structure of the first thermoelectric conversion element or thesecond thermoelectric conversion element of Example 10 may be applied tothe thermoelectric conversion element of Example 3. Further, theconfiguration and structure of the thermoelectric conversion elementdescribed in Example 4 may be applied to the thermoelectric conversionelements described in Examples 8 and 9.

For example, the thermoelectric generators according to First to FifthEmbodiments may be adapted to include a third support member attached tothe second support member using a freely stretchable elastic material(for example, silicone rubber) of superior heat conductivity. In thisway, the thermal response time constants τ of the whole generator,including the second support member, the elastic material, and the thirdsupport member, vary by the stretch and contraction of the elasticmaterial. This changes the output electrical signal, and thus enablesdetection of the movement of the third support member relative to thesecond support member. Specifically, for example, a part of thegenerator including the first support member and the second supportmember may be attached to a certain part of the arm while the thirdsupport member is attached to some other part of the arm. In this way,changes in position of different parts of the arm (for example, the bentand stretched states of the arm) can be detected. Further, theelectrical signal detecting device of an embodiment may be attached tomachines or constructions. In this way, any abnormality can be detectedupon detection of an electrical signal different from the electricalsignal that is based on a cyclic temperature change created in themachine or construction. Such detection can be used as an alternatemeans of, for example, the procedure that finds abnormalities based onthe noise of a hammer struck on a machine or construction.

It should be understood that various changes and modifications to thepresently preferred embodiments described herein will be apparent tothose skilled in the art. Such changes and modifications can be madewithout departing from the spirit and scope of the present subjectmatter and without diminishing its intended advantages. It is thereforeintended that such changes and modifications be covered by the appendedclaims.

The invention is claimed as follows:
 1. A thermoelectric generator,comprising: (A) a first support member; (B) a second support memberdisposed opposite the first support member; and (C) a firstthermoelectric conversion element disposed between the first supportmember and the second support member, wherein a relation τ_(SM1)≠τ_(SM2)is established, where τ_(SM1) is a thermal response time constant of thefirst support member, and τ_(SM2) is a thermal response time constant ofthe second support member, and wherein the first thermoelectricconversion element includes a first thermoelectric conversion member Aof p-type conductivity in contact with the second support member at afirst surface and which has a second surface opposite the first surface,and a first thermoelectric conversion member B of n-type conductivity incontact with the first support member at a first surface and which has asecond surface opposite the first surface and that is made of a materialdifferent from that of the first thermoelectric conversion member A, thefirst thermoelectric conversion member A and the first thermoelectricconversion member B being completely aligned with each other at a firstinterface between the second surface of the first thermoelectricconversion member A and the second surface of the first thermoelectricconversion member B, and disposed in direct contact with each otheralong an entirety of the first interface.
 2. The thermoelectricgenerator according to claim 1, further comprising: a secondthermoelectric conversion element disposed between the first supportmember and the second support member, wherein the second thermoelectricconversion element includes a second thermoelectric conversion member Ain contact with the first support member at a first surface and whichhas a second surface opposite the first surface, and a secondthermoelectric conversion member B in contact with the second supportmember at a first surface and which has a second surface opposite thefirst surface, the second thermoelectric conversion member A and thesecond thermoelectric conversion member B being aligned with each otherat a second interface between the second surface of the secondthermoelectric conversion member A and the second surface of the secondthermoelectric conversion member B, and disposed in direct contact witheach other along an entirety of the second interface, and wherein thefirst thermoelectric conversion element and the second thermoelectricconversion element are electrically connected to each other in series.3. The thermoelectric generator according to claim 2, furthercomprising: (A) a third thermoelectric conversion element disposedbetween the first support member and the second support member; (B) afourth thermoelectric conversion element disposed between the firstsupport member and the second support member; and (C) a first outputsection, a second output section, a third output section, and a fourthoutput section, wherein the third thermoelectric conversion elementincludes a third thermoelectric conversion member A in contact with thesecond support member at a first surface and which has a second surfaceopposite to the first surface, and a third thermoelectric conversionmember B in contact with the first support member at a first surface andwhich has a second surface opposite to the first surface, the thirdthermoelectric conversion member A and the third thermoelectricconversion member B being aligned with each other at a third interfacebetween the second surface of the third thermoelectric conversion memberA and the second surface of the third thermoelectric conversion memberB, and disposed in direct contact with each other along an entirety ofthe third interface, wherein the fourth thermoelectric conversionelement includes a fourth thermoelectric conversion member A in contactwith the first support member at a first surface and which has a secondsurface opposite to the first surface, and a fourth thermoelectricconversion member B in contact with the second support member at a firstsurface and which has a second surface opposite to the first surface,the fourth thermoelectric conversion member A and the fourththermoelectric conversion member B being aligned with each other at afourth interface between the second surface of the fourth thermoelectricconversion member A and the second surface of the fourth thermoelectricconversion member B, and disposed in direct contact with each otheralong an entirety of the fourth interface wherein the thirdthermoelectric conversion element and the fourth thermoelectricconversion element are electrically connected to each other in series,wherein the first output section is connected to the firstthermoelectric conversion element, wherein the second output section isconnected to the second thermoelectric conversion element, wherein thethird output section is connected to the third thermoelectric conversionelement, wherein the fourth output section is connected to the fourththermoelectric conversion element, and wherein the relationτ_(SM1)≠τ_(SM2) is established, where τ_(SM1) is the thermal responsetime constant of the first support member, and τ_(SM2) is the thermalresponse time constant of the second support member.
 4. Thethermoelectric generator according to claim 1, further comprising: anoutput section connected to the first thermoelectric conversion memberA.
 5. The thermoelectric generator according to claim 1, furthercomprising: an output section connected to an end portion of the firstthermoelectric conversion member A on a first support member side. 6.The thermoelectric generator according to claim 5, wherein the relationsτ_(SM1)>τ_(SM2), and S₁₂≠S₂₂ are established, where S₁₂ is an area ofthe second surface of the first thermoelectric conversion member A incontact with the second support member, provided that S₁₁>S₁₂, where S₁₁is an area of the first surface of the first thermoelectric conversionmember B in contact with the first support member, S₂₂ is an area of asecond surface of the second thermoelectric conversion member A incontact with the second support member, provided that S₂₁>S₂₂, where S₂₁is an area of a first surface of the second thermoelectric conversionmember B in contact with the first support member, τ_(SM1) is thethermal response time constant of the first support member, and τ_(SM2)is the thermal response time constant of the second support member. 7.The thermoelectric generator according to claim 5, wherein the relationsτ_(SM1)>τ_(SM2), and VL₁≠VL₂ are established, where VL₁ is a volume ofthe first thermoelectric conversion member A, VL₂ is a volume of thefirst thermoelectric conversion member B, τ_(SM1) is the thermalresponse time constant of the first support member, and τ_(SM2) is thethermal response time constant of the second support member.